Antibodies to olanzapine haptens and use thereof

ABSTRACT

Disclosed is an antibody which binds to olanzapine, which can be used to detect olanzapine in a sample such as in a competitive immunoassay method. The antibody can be used in a lateral flow assay device for point-of-care detection of olanzapine, including multiplex detection of aripiprazole, olanzapine, quetiapine, and risperidone in a single lateral flow assay device.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a Divisional of U.S. patent application Ser. No. 13/971,519, filed Aug. 20, 2013 (now abandoned), and claims the benefit of U.S. Provisional Application No. 61/691,572, filed Aug. 21, 2012, each of which is incorporated by reference herein in its entirety.

FIELD OF THE INVENTION

The present invention relates to the field of immunoassays, and in particular to antibodies that bind to olanzapine which can be used in immunoassays for detection of olanzapine.

BACKGROUND

Schizophrenia is a chronic and debilitating psychiatric disorder affecting approximately 0.45-1% of the world's population (van Os, J.; Kapur, S. “Schizophrenia” Lancet 2009, 374, 635-645). The principal goals of treatment are to achieve sustained remission from psychotic symptoms, reduce the risk and consequences of relapse, and improve patient functioning and overall quality of life. While many patients with schizophrenia are able to achieve symptom stability with the available antipsychotic medications, poor adherence to medication is a common reason for relapse with daily administered oral medications. Several studies (Abdel-Baki, A.; Ouellet-Plamondon, C.; Malla, A. “Pharmacotherapy Challenges in Patients with First-Episode Psychosis” Journal of Affective Disorders 2012, 138, S3-S14) investigating the outcomes of non-compliance have shown that patients with schizophrenia who do not take their medication as prescribed have higher rates of relapse, hospital admission and suicide as well as increased mortality. It is estimated that 40 to 75% of patients with schizophrenia have difficulty adhering to a daily oral treatment regimen (Lieberman, J. A.; Stroup, T. S.; McEvoy, J. P.; Swartz, M. S.; Rosenheck, R. A.; Perkins, D. O.; Keefe, R. S. E.; Davis, S. M.; Davis, C. E.; Lebowitz, B. D.; Severe, J.; Hsiao, J. K. “Effectiveness of Antipyschotic Drugs in Patients with Chronic Schizophrenia” New England Journal of Medicine 2005, 353(12), 1209-1223).

Therapeutic drug monitoring (TDM) is the quantification of serum or plasma concentrations of drugs, including anti-psychotic drugs, for treatment monitoring and optimization. Such monitoring permits, for example, the identification of patients that are not adhering to their medication regimen, that are not achieving therapeutic doses, that are non-responsive at therapeutic doses, that have suboptimal tolerability, that have pharmacokinetic drug-drug interactions, or that have abnormal metabolism resulting in inappropriate plasma concentrations. Considerable individual variability exists in the patient's ability to absorb, distribute, metabolize, and excrete anti-psychotic drugs. Such differences can be caused by concurrent disease, age, concomitant medication or genetic peculiarities. Different drug formulations can also influence the metabolism of anti-psychotic drugs. TDM permits dose optimization for individual patients, improving therapeutic and functional outcomes. TDM further permits a prescribing clinician to ensure compliance with prescribed dosages and achievement of effective serum concentrations.

To date, methods for determining the levels of serum or plasma concentrations of anti-psychotic drugs involve the use of liquid chromatography (LC) with UV or mass spectrometry detection, and radioimmunoassays (see, for example, Woestenborghs et al., 1990 “On the selectivity of some recently developed RIA's” in Methodological Surveys in Biochemistry and Analysis 20:241-246. Analysis of Drugs and Metabolites, Including Anti-infective Agents; Heykants et al., 1994 “The Pharmacokinetics of Risperidone in Humans: A Summary”, J Clin Psychiatry 55/5, suppl:13-17; Huang et al., 1993 “Pharmacokinetics of the novel anti-psychotic agent risperidone and the prolactin response in healthy subjects”, Clin Pharmacol Ther 54:257-268). Radioimmunoassays detect one or both of risperidone and paliperidone. Salamone et al. in U.S. Pat. No. 8,088,594 disclose a competitive immunoassay for risperidone using antibodies that detect both risperidone and paliperidone but not pharmacologically inactive metabolites. The antibodies used in the competitive immunoassay are developed against a particular immunogen. ID Labs Inc. (London, Ontario, Canada) markets an ELISA for olanzapine, another anti-psychotic drug, which also utilizes a competitive format. The Instructions For Use indicate that the assay is designed for screening purposes and intended for forensic or research use, and is specifically not intended for therapeutic use. The Instructions recommend that all positive samples should be confirmed with gas chromatography/mass spectrometry (GC-MS), and indicate that the antibody used detects olanzapine and clozapine (see ID Labs Inc., “Instructions For Use Data Sheet IDEL-F083”, Rev. Date Aug. 8, 2011). Some of these methods, namely HPLC and GC/MS, can be expensive and labor-intensive, and are generally only performed in large or specialty labs having the appropriate equipment.

A need exists for other methods for determining the levels of anti-psychotic drugs, particularly methods that can be performed in a prescribing clinician's office (where the treatment for an individual patient can be adjusted accordingly in a much more timely manner) and in other medical settings lacking LC or GC/MS equipment or requiring rapid test results.

Olanzapine is:

SUMMARY OF THE INVENTION

The present invention is directed to an isolated antibody or a binding fragment thereof, which binds to olanzapine and which: (i) is generated in response to a conjugate of a compound of Formula I and an immunogenic carrier; or (ii) competes for an epitope which is the same as an epitope bound by the antibody of (i).

wherein: R¹ is H

CH₂NH₂, CH₂NHC(O)(CH₂)_(m)CO₂H, or Z—(Y)_(p)-G; R² is H,

CH₂NH₂, CH₂NHC(O)(CH₂)_(m)CO₂H, or Z—(Y)_(p)-G; R³ is H, or W—(Y)_(p)-G; provided that two of R¹, R², R³ must be H, and further provided that R¹, R² and R³ may not all be H simultaneously; wherein: Z is selected from the group consisting of: —N(R⁴)—, —O—, —S—, -alkyl-, -alkoxyalkyl-, -aminoalkyl-, -thioalkyl-, -heteroalkyl-, alkylcarbonyl-,

wherein: W is selected from the group consisting of: —C(O)—, -alkyl-, -alkoxyalkyl-, -aminoalkyl-, -thioalkyl-, -heteroalkyl-, -alkylcarbonyl-, —N(R⁴)—,

R⁴ is H, an alkyl group, cycloalkyl group, araalkyl group or substituted or unsubstituted aryl group; Y is an organic spacer group; G is a functional linking group capable of binding to a carrier; p is 0, or 1; m is 1, 2, 3, 4, or 5; n is 1, 2, 3, 4, or 5.

Presently preferred embodiments of the antibody of the subject invention are the antibodies designated 35 and 61 generated against the compound having Formula II and the antibodies designated 3F11 and 4G9-1 generated against the compound having Formula III. Another suitable immunogen is the compound having Formula IV.

The antibodies of the subject invention can be provided in assay kits and assay devices, with a presently preferred device being a lateral flow assay device which provides for point-of-care analysis.

The invention further provides a method of producing an antibody which binds to olanzapine, the method comprising: (i) selecting a host cell for antibody production; and (ii) inoculating the host with a conjugate of a compound of Formula I and an immunogenic carrier, wherein the host produces an antibody which binds to olanzapine. Further provided is a method of producing a hybridoma cell line capable of producing a monoclonal antibody which binds to olanzapine. The method comprises: (i) selecting a host for antibody production; (ii) inoculating the host with a conjugate of a compound of Formula I and an immunogenic carrier; (iii) fusing a cell line from the inoculated host with a continuously dividing cell to create a fused cell capable of producing a monoclonal antibody which binds to olanzapine; and (iv) cloning the fused cell so as to obtain a hybridoma cell line.

The invention further provides a method of detecting olanzapine in a sample. The method comprises: (i) contacting a sample with an antibody according to the subject invention which is labeled with a detectable marker, wherein the labeled antibody and olanzapine present in the sample form a labeled complex; and (ii) detecting the labeled complex so as to detect olanzapine in the sample.

Further provided is a competitive immunoassay method for detecting olanzapine in a sample. The method comprises: (i) contacting a sample with an antibody according to the subject invention, and with olanzapine or a competitive binding partner of olanzapine, wherein one of the antibody and the olanzapine or competitive binding partner thereof is labeled with a detectable marker, and wherein sample olanzapine competes with the olanzapine or competitive binding partner thereof for binding to the antibody; and (ii) detecting the label so as to detect sample olanzapine.

Further objects, features and advantages of the present invention will be apparent to those skilled in the art from detailed consideration of the preferred embodiments that follow.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1-3 show Competitive ELISA results generated with three different mouse fusion 11.1 hybridomas;

FIG. 4 shows the competitive immunoassay format used on a lateral flow assay device;

FIG. 5 shows a typical dose response curve generated with olanzapine antibody clone 35;

FIG. 6 shows a typical dose response curve generated with olanzapine antibody clone 61;

FIG. 7 shows a typical dose response curve generated with olanzapine antibody 3F11;

FIG. 8 shows the chip design of a lateral flow assay device according to the subject invention;

FIG. 9 shows a typical dose response curve for an aripiprazole positive control generated with antibody 5C7 and a labeled aripiprazole competitive binding partner;

FIG. 10 shows a typical dose response curve for an olanzapine positive control generated with antibody 4G9-1 and a labeled olanzapine competitive binding partner;

FIG. 11 shows a typical dose response curve for a quetiapine positive control generated with antibody 11 and a labeled quetiapine competitive binding partner;

FIG. 12 shows a typical dose response curve for a risperidone positive control generated with antibody 5-9 and a labeled risperidone competitive binding partner;

FIG. 13 shows a typical dose response curve for a sample containing aripiprazole generated with aripiprazole antibody 5C7 in the presence of labeled aripiprazole competitive binding partner, with no dose response curve for olanzapine, quetiapine, or risperidone in the presence of a labeled competitive binding partner for each;

FIG. 14 shows a typical dose response curve for a sample containing olanzapine generated with olanzapine antibody 4G9-1 in the presence of a labeled olanzapine competitive binding partner, with no dose response curve for aripiprazole, quetiapine, or risperidone in the presence of a labeled competitive binding partner for each;

FIG. 15 shows a typical dose response curve for a sample containing quetiapine generated with quetiapine antibody 11 in the presence of a labeled quetiapine competitive binding partner, with no dose response curve for aripiprazole, olanzapine, or risperidone in the presence of a labeled competitive binding partner for each;

FIG. 16 shows a typical dose response curve for a sample containing risperidone generated with risperidone antibody 5-9 in the presence of a labeled risperidone competitive binding partner, with no dose response curve for aripiprazole, olanzapine, or quetiapine in the presence of a labeled competitive binding partner for each;

FIG. 17 shows a typical dose response curve for a sample containing aripiprazole generated with aripiprazole antibody 5C7 in the presence of a labeled aripiprazole competitive binding partner, with no dose response curve for olanzapine, quetiapine, or risperidone in the presence of antibody and labeled competitive binding partner for each;

FIG. 18 shows a typical dose response curve for a sample containing olanzapine generated with olanzapine antibody 4G9-1 in the presence of a labeled olanzapine competitive binding partner, with no dose response curve for aripiprazole, quetiapine, or risperidone in the presence of antibody and labeled competitive binding partner for each;

FIG. 19 shows a typical dose response curve for a sample containing quetiapine generated with quetiapine antibody 11 in the presence of labeled quetiapine competitive binding partner, with no dose response curve for aripiprazole, olanzapine, or risperidone in the presence of antibody and labeled competitive binding partner for each;

FIG. 20 shows a typical dose response curve for a sample containing risperidone generated with risperidone antibody 5-9 in the presence of a labeled risperidone competitive binding partner, with no dose response curve for aripiprazole, olanzapine, or quetiapine in the presence of antibody and labeled competitive binding partner for each;

FIG. 21 shows a comparison of the aripiprazole dose response curve generated as a positive control to the aripiprazole dose response curve generated in the multiplex format;

FIG. 22 shows a comparison of the olanzapine dose response curve generated as a positive control to the olanzapine dose response curve generated in the multiplex format;

FIG. 23 shows a comparison of the quetiapine dose response curve generated as a positive control to the quetiapine dose response curve generated in the multiplex format; and

FIG. 24 shows a comparison of the risperidone dose response curve generated as a positive control to the risperidone dose response curve generated in the multiplex format.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

The invention provides an isolated antibody which binds to olanzapine. The invention further provides an assay kit and an assay device comprising the antibody. Also provided are methods of producing the antibody and of producing a hybridoma cell line capable of producing the antibody. Further provided is a method of detecting olanzapine in a sample, including a competitive immunoassay method.

In one embodiment, the present invention is directed to an isolated antibody or a binding fragment thereof, which binds to olanzapine and which: (i) is generated in response to a conjugate of a compound of Formula I and an immunogenic carrier; or (ii) competes for an epitope which is the same as an epitope bound by the antibody of (i).

wherein: R¹ is H,

CH₂NH₂, CH₂NHC(O)(CH₂)_(m)CO₂H, or Z—(Y)_(p)-G; R² is H,

CH₂NH₂, CH₂NHC(O)(CH₂)_(m)CO₂H, or Z—(Y)_(p)-G; R³ is H, or W—(Y)_(p)-G; provided that two of R¹, R², R³ must be H, and further provided that R¹, R² and R³ may not all be H simultaneously; wherein: Z is selected from the group consisting of: —N(R⁴)—, —O—, —S—, -alkyl-, -alkoxyalkyl-, -aminoalkyl-, -thioalkyl-, -heteroalkyl-, alkylcarbonyl-,

wherein: W is selected from the group consisting of: —C(O)—, -alkyl-, -alkoxyalkyl-, -aminoalkyl-, -thioalkyl-, -heteroalkyl-, -alkylcarbonyl-, —N(R⁴)—,

R⁴ is H, an alkyl group, cycloalkyl group, araalkyl group or substituted or unsubstituted aryl group; Y is an organic spacer group; G is a functional linking group capable of binding to a carrier; p is 0, or 1; m is 1, 2, 3, 4, or 5; n is 1, 2, 3, 4, or 5.

In a further embodiment, the present invention is directed to an isolated antibody or a binding fragment thereof, which binds to olanzapine and which: (i) is generated in response to a conjugate of a compound of Formula I and an immunogenic carrier; or (ii) competes for an epitope which is the same as an epitope bound by the antibody of (i); wherein:

R¹ is H,

CH₂NH₂, CH₂NHC(O)(CH₂)_(m)CO₂H, or Z—(Y)_(p)-G; R² is H,

CH₂NH₂, CH₂NHC(O)(CH₂)_(m)CO₂H, or Z—(Y)_(p)-G; provided that either R¹ or R² must be H, and further provided that both R¹ and R² may not be H simultaneously; R³ is H; wherein: Z is selected from the group consisting of: —N(R⁴)—, —O—, —S—, -alkyl-, -alkoxyalkyl-, -aminoalkyl-, -thioalkyl-, -heteroalkyl-, -alkylcarbonyl-,

R⁴ is H, an alkyl group, cycloalkyl group, araalkyl group or substituted or unsubstituted aryl group; Y is an organic spacer group; G is a functional linking group capable of binding to a carrier; p is 0, or 1; m is 1, 2, 3, 4, or 5; n is 1, 2, 3, 4, or 5.

In a further embodiment, the present invention is directed to an isolated antibody or a binding fragment thereof, which binds to olanzapine and which: (i) is generated in response to a conjugate of a compound of Formula I and an immunogenic carrier; or (ii) competes for an epitope which is the same as an epitope bound by the antibody of (i); wherein:

R¹ is H, or CH₂NH—(Y)_(p)-G;

R² is H, or CH₂NH—(Y)_(p)-G; provided that either R¹ or R² must be H, and further provided that both R¹ and R² may not be H simultaneously;

R³ is H,

wherein:

Y is an organic spacer group;

G is a functional linking group capable of binding to a carrier;

p is 1.

In a further embodiment, the present invention is directed to an isolated antibody or a binding fragment thereof, which binds to olanzapine and which: (i) is generated in response to a conjugate of a compound of Formula I and an immunogenic carrier; or (ii) competes for an epitope which is the same as an epitope bound by the antibody of (i); wherein:

R¹ is H,

CH₂NH₂, or CH₂NHC(O)(CH₂)_(m)CO₂H; R² is H,

CH₂NH₂, or CH₂NHC(O)(CH₂)_(m)CO₂H; provided that either R¹ or R² must be H, and further provided that both R¹ and R² may not be H simultaneously; R³ is H; m is 1, 2, 3, 4, or 5; n is 1, 2, 3, 4, or 5.

In a further embodiment, the present invention is directed to an isolated antibody or a binding fragment thereof, which binds to olanzapine and which: (i) is generated in response to a conjugate of a compound of Formula I and an immunogenic carrier; or (ii) competes for an epitope which is the same as an epitope bound by the antibody of (i); wherein:

R¹ is H,

CH₂NH₂, or CH₂NHC(O)(CH₂)_(m)CO₂H; R² is H,

CH₂NH₂, or CH₂NHC(O)(CH₂)_(m)CO₂H; provided that either R¹ or R² must be H, and further provided that both R¹ and R² may not be H simultaneously; R³ is H; m is 1, 2, 3, 4, or 5; n is 1, 2, 3, 4, or 5.

In a preferred embodiment, the present invention is directed to an isolated antibody or a binding fragment thereof, which binds to olanzapine and which: (i) is generated in response to a conjugate of a compound of Formula V and an immunogenic carrier; or (ii) competes for an epitope which is the same as an epitope bound by the antibody of (i).

In a preferred embodiment, the present invention is directed to an isolated antibody or a binding fragment thereof, which binds to olanzapine and which: (i) is generated in response to a conjugate of a compound of Formula VI and an immunogenic carrier; or (ii) competes for an epitope which is the same as an epitope bound by the antibody of (i).

In a preferred embodiment, the present invention is directed to an isolated antibody or a binding fragment thereof, which binds to olanzapine and which: (i) is generated in response to a conjugate of a compound of Formula VII and an immunogenic carrier; or (ii) competes for an epitope which is the same as an epitope bound by the antibody of (i).

In a preferred embodiment, the present invention is directed to an isolated antibody or a binding fragment thereof, which binds to olanzapine and which: (i) is generated in response to a conjugate of a compound of Formula VIII and an immunogenic carrier; or (ii) competes for an epitope which is the same as an epitope bound by the antibody of (i).

In a preferred embodiment, the present invention is directed to an isolated antibody or a binding fragment thereof, which binds to olanzapine and which: (i) is generated in response to a conjugate of a compound of Formula IX and an immunogenic carrier; or (ii) competes for an epitope which is the same as an epitope bound by the antibody of (i).

In a preferred embodiment, the present invention is directed to an isolated antibody or a binding fragment thereof, which binds to olanzapine and which: (i) is generated in response to a conjugate of a compound of Formula X and an immunogenic carrier; or (ii) competes for an epitope which is the same as an epitope bound by the antibody of (i).

Preferably, the antibody of the subject invention is generated in response to a conjugate of a compound selected from the compounds of: Formula I, Formula V, Formula VI, Formula VII, Formula VIII, Formula IX, and Formula X; and an immunogenic carrier.

Further details of the compounds described by the formulas above and the conjugates formed by the compounds and an immunogenic carrier are provided in the section below entitled “Compounds, Conjugates and Immunogens”.

Further details of the antibodies of the subject invention are provided in the section below entitled “Antibodies”.

The subject invention further provides an assay kit comprising the antibody, as well as an assay device comprising the antibody. Preferably, the assay device is a lateral flow assay device. Further details of the assay kits and assay devices are provided below in the section entitled “Assay Kits and Devices”.

The invention further provides a method of producing an antibody which binds to olanzapine, the method comprising: (i) selecting a host cell for antibody production; and (ii) inoculating the host with a conjugate of a compound of Formula I and an immunogenic carrier, wherein the host produces an antibody which binds to olanzapine. In additional embodiments, the conjugate used in the method can be a conjugate of a compound selected from the compounds of: Formula V, Formula VI, Formula VII, Formula VIII, Formula IX, and Formula X; and an immunogenic carrier. Further details on the production of the antibodies of the subject invention are provided in the section below entitled “Antibodies”.

Further provided is a method of producing a hybridoma cell line capable of producing a monoclonal antibody which binds to olanzapine. The method comprises: (i) selecting a host for antibody production; (ii) inoculating the host with a conjugate of a compound of Formula I and an immunogenic carrier; (iii) fusing a cell line from the inoculated host with a continuously dividing cell to create a fused cell capable of producing a monoclonal antibody which binds to olanzapine; and (iv) cloning the fused cell so as to obtain a hybridoma cell line. In additional embodiments, the conjugate used in the method can be a conjugate of a compound selected from the compounds of: Formula V, Formula VI, Formula VII, Formula VIII, Formula IX, and Formula X; and an immunogenic carrier. Further details of the production of hybridomas in accordance with the subject invention are provided in the section below entitled “Antibodies”.

The invention further provides a method of detecting olanzapine in a sample. The method comprises: (i) contacting a sample with an antibody according to the subject invention which is labeled with a detectable marker, wherein the labeled antibody and olanzapine present in the sample form a labeled complex; and (ii) detecting the labeled complex so as to detect olanzapine in the sample. Further details of the method of detecting olanzapine in accordance with the subject invention are provided in the section below entitled “Immunoassays”.

Further provided is a competitive immunoassay method for detecting olanzapine in a sample. The method comprises: (i) contacting a sample with an antibody according to the subject invention, and with olanzapine or a competitive binding partner of olanzapine, wherein one of the antibody and the olanzapine or competitive binding partner thereof is labeled with a detectable marker, and wherein sample olanzapine competes with the olanzapine or competitive binding partner thereof for binding to the antibody; and (ii) detecting the label so as to detect sample olanzapine. Further details of the competitive immunoassay method of detecting olanzapine in accordance with the subject invention are provided in the section below entitled “Immunoassays”.

In a preferred embodiment of the subject invention, the detection of olanzapine is accompanied by the detection of one or more analytes in addition to olanzapine. Preferably the one or more analytes are anti-psychotic drugs other than olanzapine, and more preferably the anti-psychotic drugs other than olanzapine are selected from the group consisting of: aripiprazole, risperidone, paliperidone, quetiapine, and metabolites thereof.

As discussed above, the antibodies of the subject invention can be used in assays to detect the presence and/or amount of the anti-psychotic drug in patient samples. Such detection permits therapeutic drug monitoring enabling all of the benefits thereof. Detection of levels of anti-psychotic drugs may be useful for many purposes, each of which represents another embodiment of the subject invention, including: determination of patient adherence or compliance with prescribed therapy; use as a decision tool to determine whether a patient should be converted from an oral anti-psychotic regimen to a long-acting injectable anti-psychotic regimen; use as a decision tool to determine if the dose level or dosing interval of oral or injectable anti-psychotics should be increased or decreased to ensure attainment or maintenance of efficacious or safe drug levels; use as an aid in the initiation of anti-psychotic drug therapy by providing evidence of the attainment of minimum pK levels; use to determine bioequivalence of anti-psychotic drug in multiple formulations or from multiple sources; use to assess the impact of polypharmacy and potential drug-drug interactions; and use as an indication that a patient should be excluded from or included in a clinical trial and as an aid in the subsequent monitoring of adherence to clinical trial medication requirements.

Compounds, Conjugates and Immunogens

In relation to the compounds and conjugates and immunogens, the following abbreviations are used: AMAS is N-(α-maleimidoacetoxy) succinimide ester; BTG is bovine thyroglobulin; Bu₃N is tributylamine; DCC is dicyclohexylcarbodiimide; DCM is dichloromethane; DIEA is diisopropylethylamine; DMF is N,N-dimethylformamide; DMSO is dimethylsulfoxide; EDTA is ethylenediaminetetraceticacid; KLH is keyhole limpet hemocyanin; SATA is N-succinimidyl S-acetylthioacetate; TEA is triethylamine; THF is tetrahydrofuran; TFA is trifluoroacetic acid; r.t. is room temperature; DIC is diisopropylcarbodiimide; DMAP is N,N-dimethyl-4-aminopyridine; EDC is 1-ethyl-3(3-dimethylaminopropyl) carbodiimidehydrochloride; NHS is N-hydroxysuccinimide; TFP is Tetrafluorophenyl; PNP is p-nitrophenyl; TBTU is O-(Benzotriazol-1-yl)-N,N,N′,N′-tetramethyluronium tetrafluoroborate; HOBT is N-Hydroxybenzotriazole; DEPBT is 3-(diethoxyphosphoryloxy)-1,2,3-benzotrazin-4(3H)-one; BOP-Cl is Bis(2-oxo-3-oxazolidinyl)phosphonic chloride; and DTT is dithioerythritol.

The term “conjugate” refers to any substance formed from the joining together of separate parts. Representative conjugates include those formed by the joining together of a small molecule, such as the compounds of Formula I, and a large molecule, such as a carrier or a polyamine polymer, particularly a protein. In the conjugate the small molecule may be joined at one or more active sites on the large molecule.

The term “hapten” refers to a partial or incomplete antigen. A hapten is a protein-free substance, which is not capable of stimulating antibody formation, but which does react with antibodies. The antibodies are formed by coupling a hapten to a high molecular weight immunogenic carrier, and then injecting this coupled product, i.e., an immunogen, into a human or animal subject.

The term “immunogen” refers to a substance capable of eliciting, producing, or generating an immune response in an organism.

An “immunogenic carrier,” as used herein, is an immunogenic substance, commonly a protein, that can join at one or more positions with haptens, thereby enabling the production of antibodies that can bind with these haptens. Examples of immunogenic carrier substances include, but are not limited to, proteins, glycoproteins, complex polyamino-polysaccharides, particles, and nucleic acids that are recognized as foreign and thereby elicit an immunologic response from the host. The polyamino-polysaccharides may be prepared from polysaccharides using any of the conventional means known for this preparation.

Various protein types may be employed as immunogenic carriers, including without limitation, albumins, serum proteins, lipoproteins, etc. Illustrative proteins include bovine serum albumin, keyhole limpet hemocyanin, egg ovalbumin, bovine thyroglobulin, fraction V human serum albumin, rabbit albumin, pumpkin seed globulin, diphtheria toxoid, tetanus toxoid, botilinus toxin, succinylated proteins, and synthetic poly(aminoacids) such as polylysine.

Immunogenic carriers can also include poly amino-polysaccharides, which are a high molecular weight polymers built up by repeated condensations of monosaccharides. Examples of polysaccharides are starches, glycogen, cellulose, carbohydrate gums such as gum arabic, agar, and so forth. The polysaccharide also contains poly(amino acid) residues and/or lipid residues.

The immunogenic carrier can also be a poly(nucleic acid) either alone or conjugated to one of the above mentioned poly(amino acids) or polysaccharides.

The immunogenic carrier can also include solid particles. The particles are generally at least about 0.02 microns (μm) and not more than about 100 μm, and usually about 0.05 μm to 10 μm in diameter. The particle can be organic or inorganic, swellable or non-swellable, porous or non-porous, optimally of a density approximating water, generally from about 0.7 to 1.5 g/mL, and composed of material that can be transparent, partially transparent, or opaque. The particles can be biological materials such as cells and microorganisms, including non-limiting examples such as erythrocytes, leukocytes, lymphocytes, hybridomas, Streptococcus, Staphylococcus aureus, E. coli, and viruses. The particles can also be comprised of organic and inorganic polymers, liposomes, latex, phospholipid vesicles, or lipoproteins.

The term “derivative” refers to a chemical compound or molecule made from a parent compound by one or more chemical reactions.

The term “analogue” of a chemical compound refers to a chemical compound that contains a chain of carbon atoms and the same particular functional groups as a reference compound, but the carbon chain of the analogue is longer or shorter than that of the reference compound.

A “label,” “detector molecule,” “reporter” or “detectable marker” is any molecule which produces, or can be induced to produce, a detectable signal. The label can be conjugated to an analyte, immunogen, antibody, or to another molecule such as a receptor or a molecule that can bind to a receptor such as a ligand, particularly a hapten or antibody. A label can be attached directly or indirectly by means of a linking or bridging moiety. Non-limiting examples of labels include radioactive isotopes (e.g., ¹²⁵I), enzymes (e.g. β-galactosidase, peroxidase), enzyme fragments, enzyme substrates, enzyme inhibitors, coenzymes, catalysts, fluorophores (e.g., rhodamine, fluorescein isothiocyanate or FITC, or Dylight 649), dyes, chemiluminescers and luminescers (e.g., dioxetanes, luciferin), or sensitizers.

As used herein, a “spacer” refers to a portion of a chemical structure which connects two or more substructures such as haptens, carriers, immunogens, labels or binding partners through a functional linking group. These spacer groups are composed of the atoms typically present and assembled in ways typically found in organic compounds and so may be referred to as “organic spacing groups”. The chemical building blocks used to assemble the spacers will be described hereinafter in this application. Among the preferred spacers are straight or branched, saturated or unsaturated carbon chains. These carbon chains may also include one or more heteroatoms within the chain, one or more heteroatoms replacing one or more hydrogens of any carbon atom in the chain, or at the termini of the chains. By “heteroatoms” is meant atoms other than carbon which are chosen from the group consisting of oxygen, nitrogen, phosphorous and sulfur, wherein the nitrogen, phosphorous and sulfur atoms may exist in any oxidation state and may have carbon or other heteroatoms bonded to them. The spacer may also include cyclic or aromatic groups as part of the chain or as a substitution on one of the atoms in the chain.

The number of atoms in the spacing group is determined by counting the atoms other than hydrogen. The number of atoms in a chain within a spacing group is determined by counting the number of atoms other than hydrogen along the shortest route between the substructures being connected. Preferred chain lengths are between 1 to 20 atoms.

A “functional linking group” refers to a reactive group that is present on a hapten and may be used to provide an available reactive site through which the hapten portion may be coupled to another moiety through formation of a covalent chemical bond to produce a conjugate of a hapten with another moiety (such as a label or carrier). The hapten may be linked in this way to a moiety such as biotin to form a competitive binding partner.

Spacer groups may be used to link the hapten to the carrier. Spacers of different lengths allow one to attach the hapten with differing distances from the carrier for presentation to the immune system of the animal or human being immunized for optimization of the antibody formation process. Attachment to different positions in the hapten molecule allows the opportunity to present specific sites on the hapten to the immune system to influence antibody recognition. The spacer may contain hydrophilic solubilizing groups to make the hapten derivative more soluble in aqueous media. Examples of hydrophilic solubilizing groups include but are not limited to polyoxyalkyloxy groups, for example, polyethylene glycol chains; hydroxyl, carboxylate and sulfonate groups.

The term “nucleophilic group” or “nucleophile” refers to a species that donates an electron-pair to form a chemical bond in a reaction. The term “electrophilic group” or “electrophile” refers to a species that accepts an electron-pair from a nucleophile to form a chemical bond in a reaction.

The term “substituted” refers to substitution of an atom or group of atoms in place of a hydrogen atom on a carbon atom in any position on the parent molecule. Non limiting examples of substituents include halogen atoms, amino, hydroxy, carboxy, alkyl, aryl, heteroalkyl, heteroaryl, cyano, alkoxy, nitro, aldehyde and ketone groups.

The term “alkyl” refers to saturated or unsaturated linear and branched chain radicals of up to 12 carbon atoms, unless otherwise indicated, and is specifically intended to include radicals having any degree or level of saturation. Alkyl includes, but is not limited to, methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, tert-butyl, pentyl, isopentyl, hexyl, isohexyl, heptyl, octyl, 2,2,4-trimethylpentyl, nonyl, decyl, undecyl and dodecyl.

The term “cycloalkyl” refers to a saturated or partially unsaturated monocyclic or bicyclic hydrocarbon ring radical composed of from 3 to 10 carbon atoms. Alkyl substituents may optionally be present on the ring. Examples include cyclopropyl, 1,1-dimethyl cyclobutyl, 1,2,3-trimethylcyclopentyl, cyclohexyl and cyclohexenyl.

The term “heteroalkyl” refers to an alkyl group that includes one or more heteroatoms within the chain, one or more heteroatoms replacing one or more hydrogens of any carbon atom in the chain, or at termini of the chains.

The term “aminoalkyl” refers to at least one primary or secondary amino group bonded to any carbon atom along an alkyl chain.

The term “alkoxy” refers to straight or branched chain radicals of up to 12 carbon atoms, unless otherwise indicated, bonded to an oxygen atom. Examples include but are not limited to methoxy, ethoxy, propoxy, isopropoxy and butoxy.

The term “alkoxyalkyl” refers to at least one alkoxy group bonded to any carbon atom along an alkyl chain.

The term “thioalkyl” refers to at least one sulfur group bonded to any carbon atom along an alkyl chain. The sulfur group may be at any oxidation state and includes sulfoxides, sulfones and sulfates.

The term “carboxylate group” includes carboxylic acids and alkyl, cycloalkyl, aryl or aralkyl carboxylate esters.

The term “alkylcarbonyl” refers to a group that has a carbonyl group bonded to any carbon atom along an alkyl chain.

The term “heteroaryl” refers to 5- to 7-membered mono- or 8- to 10-membered bicyclic aromatic ring radicals, any ring of which may consist of from one to four heteroatoms selected from N, O or S where the nitrogen and sulfur atoms can exist in any allowed oxidation state. Examples include benzimidazolyl, benzothiazolyl, benzothienyl, benzoxazolyl, furyl, imidazolyl, isothiazolyl, isoxazolyl, oxazolyl, pyrazinyl, pyrazolyl, pyridyl, pyrimidinyl, pyrrolyl, quinolinyl, thiazolyl and thienyl.

The term “aryl” refers to monocyclic or bicyclic aromatic ring radicals containing from 6 to 12 carbons in the ring. Alkyl substituents may optionally be present on the ring. Examples include phenyl, biphenyl and napththalene.

The term “aralkyl” refers to a C₁₋₆ alkyl group containing an aryl substituent. Examples include benzyl, phenylethyl or 2-naphthylmethyl.

The term “acyl” refers to the group —C(O)R_(a), where R_(a) is hydrogen, alkyl, cycloalkyl, heteroalkyl, aryl, aralkyl and heteroaryl. An “acylating agent” adds the —C(O)R_(a) group to a molecule.

The term “sulfonyl” refers to the group —S(O)₂R_(b), where R_(b) is hydrogen, alkyl, cycloalkyl, heteroalkyl, haloalkyl, aryl, aralkyl and heteroaryl. A “sulfonylating agent” adds the —S(O)₂R_(a) group to a molecule.

Spacers bearing reactive functional linking groups for the attachment of haptens to carrier moieties may be prepared by a wide variety of methods. The spacer may be formed using a molecule that is differentially functionalized or activated with groups at either end to allow selective sequential reaction with the hapten and the carrier, but the same reactive moiety may also be used at both ends. The groups selected for reaction with the hapten and the functional linking group to be bound to the carrier are determined by the type of functionality on the hapten and the carrier that the hapten is to be bonded with. Spacers and methods of attachment to haptens and carriers include but are not limited to those described by Brinkley, M., A., Bioconjugate Chem. 1992, 3:2-13, Hermanson, Greg T., Bioconjugate Techniques, Academic Press, London, Amsterdam, Burlington, Mass., USA, 2008 and Thermo Scientific Pierce Crosslinking Technical Handbook; available for download or hard copy request from Thermo Scientific 3747 N Meridian Rd, Rockford, Ill. USA 61101, ph 800-874-3723 or at: http://www.piercenet.com/ and references within. Many differentially activated molecules for formation of spacer groups are commercially available from vendors, for example Thermo Scientific.

For haptens bearing an amino group, modes of attachment of the spacer to the hapten include reaction of the amine on the hapten with a spacer building block bearing an acyl halide or active ester. “Active esters” are defined as esters that undergo reaction with a nucleophilic group, for example an amino group, under mild conditions to form a stable linkage. A stable linkage is defined as one that remains intact under conditions of further use, for example subsequent synthetic steps, use as an immunogen, or in a biochemical assay. A preferred example of a stable linkage is an amide bond. Active esters and methods of formation are described by Benoiton, N. L., in Houben-Weyl, Methods of Organic Chemistry, Thieme Stuttgart, N.Y., vol E22 section 3.2:443 and Benoiton, N. L., Chemistry of Peptide Synthesis, Taylor and Francis, NY, 2006. Preferred active esters include p-nitrophenyl ester (PNP), N-hydroxysuccinimide ester (NHS) and tetrafluorophenyl ester (TFP). Acyl halides may be prepared by many methods known to one skilled in the art for example, reaction of the carboxylic acid with thionyl chloride or oxalyl chloride, see: Fieser, L. F. and Fieser, M. Reagents for Organic Synthesis, John Wiley and Sons, NY, 1967 and references within. These may be converted to other active esters such as p-nitrophenyl esters (PNP) which may also be used in active bi-functional spacers as described by Wu et. al, Organic Letters, 2004, 6 (24):4407. N-hydroxysuccinimide (NHS) esters may be prepared by reaction of N,N-disuccinimidyl carbonate (CAS 74124-79-1) with the carboxylic acid of a compound in the presence of an organic base such as triethylamine or diisopropylethylamine in an aprotic solvent under anhydrous conditions as described in Example 35 of WO2012012595 or by using N-hydroxysuccinimide and dicyclohexylcarbodiimide (DCC) or other dehydrating agent, under anhydrous conditions. Tetrafluorophenyl esters (TFP) may be prepared by reaction of carboxylic acids with 2,3,5,6-tetrafluorophenyltrifluoroacetate in the presence of an organic base such as triethylamine or diisopropylethylamine in an aprotic solvent under anhydrous conditions as reported by Wilbur, et. al, Bioconjugate Chem., 2004, 15(1):203. One skilled in the art will recognize that spacers shown in Table 1, among others, can be obtained using known methods and attached to amino-bearing haptens utilizing routine optimization of reaction conditions. These spacers allow attachment of the hapten to a thiol group on a carrier.

TABLE 1

Reasonable values for m and n are between 1 and 10

Direct coupling of the amine on the hapten and a carboxylic acid functionality on the spacer building block in the presence of a coupling agent may also be used as a mode of attachment. Preferred reagents are those typically used in peptide synthesis. Peptide coupling reagents include but are not limited to O-(Benzotriazol-1-yl)-N,N,N′,N′-tetramethyluronium tetrafluoroborate (TBTU, CAS #125700-67-6), see: Pruhs, S., Org. Process. Res. Dev. 2006, 10:441; N-Hydroxybenzotriazole (HOBT, CAS #2592-95-2) with a carbodiimide dehydrating agent, for example N—N-dicyclohexylcarbodiimide (DCC), diisopropylcarbodiimide (DIC), or 1-ethyl-3(3-dimethylaminopropyl)carbodiimidehydrochloride (EDC), see: König W., Geiger, R. Chem. Ber., 1970, 103 (3):788; 3-(diethoxyphosphoryloxy)-1,2,3-benzotrazin-4(3H)-one (DEPBT, CAS #165534-43-0), see: Liu, H. et. al., Chinese Chemical Letters, 2002, 13(7):601; Bis(2-oxo-3-oxazolidinyl)phosphonic chloride; (BOP-Cl, CAS #68641-49-6), see: Diago-Meseguer, J et. al. Synthesis, 1980, 7:547-51 and others described in detail by Benoiton in Chemistry of Peptide Synthesis, CRC Press, Boca Raton, Fla., 2005, Chapter 2, and the technical bulletin provided by Advanced Automated Peptide Protein Technologies (aapptec), 6309 Shepardsville Rd., Louisville Ky. 40228, ph 888 692 9111; www.aapptec.com, and references within. These methods create a stable amide linkage attaching the hapten to the spacer. Examples of spacers that can be obtained using known methods and attached to amino-bearing haptens utilizing routine optimization of reaction conditions employing the methods described and cited above are shown, but not limited to those in Table 2. These spacers allow attachment of the hapten to a thiol group on a carrier.

TABLE 2

reasonable range for n is between 1-10

Spacers may also be constructed in a step-wise fashion by sequential attachment of appropriate chemical groups to the hapten including the step of forming the functional linking group that is capable of binding to the carrier. See illustrative examples under General Reaction Schemes.

Additionally, when the hapten has a nucleophilic group, for example a thiol group, an amino group or a hydroxyl group which will become the point of attachment of the spacer, the spacer may also be constructed by alkylation of the thiol, amine or hydroxyl group. Any alkyl group that is appropriately substituted with a moiety capable of undergoing a substitution reaction, for example, an alkyl halide, or sulfonic acid ester such as p-Toluenesulfonate, may be used to attach the spacer. Many examples of alkylation reactions are known to one skilled in the art and specific examples may be found in the general chemical literature and optimized through routine experimentation. A discussion of alkylation reactions with many references can be found in Chapter 10 of March's Advanced Organic Chemistry, Smith, M. B., and March, J., John Wiley & sons, Inc. NY, 2001. Other linkages may also be employed such as reaction of the nucleophilic moiety, for example an amine, on the hapten with an isocyanate to form a urea or reaction with an isothiocyanate to form a thiourea linkage, see: Li, Z., et. al., Phosphorus, Sulfur and Silicon and the Related Elements, 2003, 178(2):293-297. Spacers may be attached to haptens bearing hydroxyl groups via reaction with isocyanate groups to form carbamate or urethane linkages. The spacer may be differentially activated with the isocyanate functional group on one end and a functional linking group capable of reacting with the carrier, see: Annunziato, M. E., Patel, U. S., Ranade, M. and Palumbo, P. S., Bioconjugate Chem., 1993, 4:212-218.

For haptens bearing a carboxylic acid group, modes of attachment of a spacer portion to the hapten include activation of the carboxylic acid group as an acyl halide or active ester, examples of which are shown in Table 3, preparation of which are described previously, followed by reaction with an amino (—NH₂—), hydrazino (—NH—NH₂—), hydrazido (—C(O)—NH—NH₂—) or hydroxyl group (—OH) on the spacer portion to form an amide, hydrazide, diacylhydrazine or ester linkage, or direct coupling of the carboxylic acid group with an amino group on the spacer portion or directly on the carrier with a peptide coupling reagent and/or carbodiimide dehydrating reagent, described previously, examples of which are shown in Tables 4 and 5. Procedures found in references cited previously for formation of activated esters and use of peptide coupling agents may be employed for attachment of carboxylic acid-bearing haptens to spacer building blocks and protein carriers with available amino groups utilizing routine optimization of reaction conditions.

TABLE 3

TABLE 4

TABLE 5

Other electrophilic groups may be present on the hapten to attach the spacer, for example, a sulfonyl halide

or electrophilic phosphorous group, for example:

See: Malachowski, William P., Coward, James K., Journal of Organic Chemistry, 1994, 59 (25):7616 or:

R_(c) is alkyl, cycloalkyl, aryl, substituted aryl, aralkyl. See: Aliouane, L., et. al, Tetrahedron Letters, 2011, 52(28):8681.

Haptens that bear aldehyde or ketone groups may be attached to spacers using methods including but not limited to reaction with a hydrazide group H₂N—NH—C(O)— on the spacer to form an acylhydrazone, see: Chamow, S. M., Kogan, T. P., Peers, D. H., Hastings, R. C., Byrn, R. A. and Askenaszi, A., J. Biol. Chem., 1992, 267(22): 15916. Examples of bifunctional hydrazide spacer groups that allow attachment to a thiol group on the carrier are shown in Table 6.

TABLE 6

Haptens may also contain thiol groups which may be reacted with the carrier provided that the carrier has been modified to provide a group that may react with the thiol. Carrier groups may be modified by methods including but not limited to attachment of a group containing a maleimide functional group by reaction of an amino group on the carrier with N-Succinimidyl maleimidoacetate, (AMAS, CAS #55750-61-3), Succinimidyl iodoacetate (CAS #151199-81-4), or any of the bifunctional spacer groups shown in Table 1 to introduce a group which may undergo a reaction resulting in attachment of the hapten to the carrier.

The functional linking group capable of forming a bond with the carrier may be any group capable of forming a stable linkage and may be reactive to a number of different groups on the carrier. The functional linking group may preferably react with an amino group, a carboxylic acid group or a thiol group on the carrier, or derivative thereof. Non-limiting examples of the functional linking group are a carboxylic acid group, acyl halide, active ester (as defined previously), isocyanate, isothiocyanate, alkyl halide, amino group, thiol group, maleimide group, acrylate group (H₂C═CH—C(O)—) or vinyl sulfone group H₂C═CH—SO₂—) See: Park, J. W., et. al., Bioconjugate Chem., 2012, 23(3): 350. The functional linking group may be present as part of a differentially activated spacer building block that may be reacted stepwise with the hapten and the resulting hapten derivative may then be reacted with the carrier. Alternatively, the hapten may be derivatized with a spacer that bears a precursor group that may be transformed into the functional linking group by a subsequent reaction. When the functional linking group on the spacer is an amine or a carboxylic acid group, the coupling reaction with the carboxylic acid group or amine on the carrier may be carried out directly through the use of peptide coupling reagents according to procedures in the references cited above for these reagents.

Particular disulfide groups, for example, pyridyldisulfides, may be used as the functional linking group on the spacer which may undergo exchange with a thiol group on the carrier to from a mixed disulfide linkage, see: Ghetie, V., et al., Bioconjugate Chem., 1990, 1:24-31. These spacers may be attached by reaction of the amine-bearing hapten with an active ester which is attached to a spacer bearing the pyridyldisulfide group, examples of which include but are not limited to those shown in Table 7.

TABLE 7

Most often the carrier is a protein and the ε-amino groups of the lysine residues may be used for attachment, either directly by reaction with an amine-reactive functional linking group or after derivitization with a thiol-containing group, including N-Succinimidyl S-Acetylthioacetate, (SATA, CAS 76931-93-6), or an analogue thereof, followed by cleavage of the actetate group with hydroxylamine to expose the thiol group for reaction with the functional linking group on the hapten. Thiol groups may also be introduced into the carrier by reduction of disulfide bonds within protein carriers with mild reducing reagents including but not limited to 2-mercaptoethylamine, see: Bilah, M., et. al., Bioelectrochemistry, 2010, 80(1):49, phosphine reagents, see: Kirley, T. L., Analytical Biochemistry, 1989, 180(2):231 or dithioerythritol (DTT, CAS 3483-12-3) Cleland, W., Biochemistry, 1964, 3:480-482.

General Reaction Schemes

Compounds useful for producing antibodies according to the subject invention can be synthesized in accordance with the general synthetic methods described below. Compounds of Formula (I) can be prepared by methods known to those who are skilled in the art. The following reaction schemes are only meant to represent examples of the invention and are in no way meant to be a limit of the invention.

Compounds of Formula I where R² is CH₂NHC(O)(CH₂)_(m)CO₂H may be made according to Scheme 1. Reaction of (1-methyl-4-(2-methyl-10H-benzo[b]thieno[2,3-e][1,4]diazepin-4-yl)piperazin-2-yl)methanamine, prepared as described in Example 1, Step I, proceeds with a cyclic anhydride compound, such as succinic anhydride or glutaric anhydride, in a solvent such as pyridine, at temperatures ranging from room temperature to 60° C., for about 48 hours. Those skilled in the art will recognize that the same chemistry may be used to create compounds of Formula I where R¹ is CH₂NHC(O)(CH₂)_(m)CO₂H.

Compounds of Formula I where R² is

may be made according to Scheme 2. Compounds of Formula I, where R² is CH₂NHC(O)(CH₂)_(m)CO₂H, prepared as described in Scheme 1, are treated with N-t-butoxycarbonylpiperazine, diethyl cyanophosphonate, and a base, such as diisopropylethylamine. The reaction is carried out in a solvent, such as dichloromethane, for about 2 hours at room temperature. Deprotection of the piperazinyl group is accomplished with trifluoroacetic anhydride as described in Scheme 2, followed by reaction with an appropriate anhydride, such as succinic anhydride or maleic anhydride, in the presence of a suitable base such as diisopropylethylamine. Those skilled in the art will recognize that the same chemistry may be used to create compounds of Formula I where R¹ is

Compounds of Formula I where R¹ is

may be made according to Scheme 3. The maleimide may be introduced by any method known in the art. Maleimide functionalizing groups such as 2,5-dioxopyrrolidin-1-yl 2-(2,5-dioxo-2,5-dihydro-1H-pyrrol-1-yl)acetate where m is 1, may be used in a solvent such as DMF or CH₂Cl₂, and a base, such as tributylamine or triethylamine. Alternatively, the deprotected piperazinyl group described in Scheme 2 may be elaborated with a maleimide functionality, as described in Scheme 3 to give compounds of Formula I where R¹ is

Those skilled in the art will recognize that the same chemistry may be used to create compounds of Formula I where R² is

Compounds in which the spacer and linking group are attached to the unsubstituted secondary nitrogen in the diazepine ring of olanzapine may be obtained by the reactions depicted in schemes 4 to 8. Acylation of the nitrogen is described by Su, J. et. al, Bioorganic and Med. Chem. Letters, 2006, 16:4548. Use of the mono ester mono acid chloride of succinic acid in the presence of a base, under anhydrous conditions in an aprotic solvent, provides an intermediate, the ester functionality of which may be hydrolyzed using standard conditions known to one skilled in the art, for example, aqueous base, to provide a hapten that may be further elaborated into an immunogen by methods previously described herein and illustrated by examples of this disclosure.

Su, et. al., above, also report preparation of sulfonamides. Through use of a functionalized sulfonylchloride in the presence of a base, under anhydrous conditions in an aprotic solvent, as shown in Scheme 5, a carboxy hapten may be prepared and transformed into an immunogen by methods previously described herein and illustrated by examples of this disclosure.

Su, et. al., above, also teach methods for preparation of a hydrazine as shown in Scheme 6, through diazotization of the ring nitrogen with a nitrite ester followed by reduction with zinc in acetic acid. The resulting hydrazine may be further functionalized in a number of ways as shown in Scheme 7. Reaction with a bifunctional spacer building block, for example AMAS, in the presence of an amine base, for example, tribuytlamine, in a solvent such as DMF as described elsewhere herein, may provide a maleimide hapten that may be attached to a carrier through reaction with a thiol group. Sulfonylation in the presence of base with a functionalized sulfonyl chloride, for example, m-carboxybenzenesulfonylchloride may provide a sulfonylhydrazide that bears a carboxy group for attachment to a carrier by methods previously described herein and illustrated by examples of this disclosure. Additionally, the hydrazine may be reacted with a functionalized aldehyde or ketone, for example, levulinic acid, as described in U.S. Pat. No. 4,022,780, with a catalytic amount of acid under conditions where water generated by the condensation is removed, to provide a hydrazone as shown in scheme 7. The hydrazone may be subsequently reduced using sodium cyanoborohydride in the method of Su, J. et al., previously referenced, to provide a saturated derivative.

Direct alkylation of the ring nitrogen as shown in Scheme 8, may also be accomplished using the method described in U.S. Pat. No. 6,034,078 to append an alkyl group directly to olanzapine. Though use of a functionalized alkyl halide, for example, 4-chloromethylbutyrate, one may obtain an intermediate which, through hydrolysis using standard conditions known to one skilled in the art, may provide a hapten that may be further elaborated into an immunogen by methods previously described herein and illustrated by examples of this disclosure.

Maleimide functionalized haptens wherein R¹ or R² is

may be conjugated to proteins according to the method shown in Scheme 9. Activation of protein lysine residues by acylation of the epsilon-nitrogen with N-succinimidyl S-acetylthioacetate (SATA), followed by subsequent hydrolysis of the S-acetyl group with hydroxylamine produces a nucleophilic sulfhydryl group. Conjugation of the sulfhydryl activated protein with the maleimide derivatized hapten (prepared as described in general scheme 3) proceeds via a Michael addition reaction. Suitable proteins are known to those skilled in the art and include keyhole limpet hemocyanin, bovine thyroglobulin, and ovalbumin. The same methodology may be used to conjugate proteins to maleimide functionalized haptens where R¹ or R² is

Carboxylic acid functionalized haptens, wherein R¹ or R² is CH₂NHC(O)(CH₂)_(m)CO₂H, may be conjugated to proteins according to the method shown in Scheme 10. Reaction with N-hydroxysuccinimide and a suitable coupling agent, such as dicyclohexylcarbodiimide, and a base, such as tributyl amine, in a solvent such as DMF, at a temperature of about 20° C., for about 18 hrs activates the carboxylic acid with the hydroxypyrrolidine-2,5-dione leaving group. The activated linker and hapten may then be conjugated to a protein in a solvent, such as a pH 7.5 phosphate buffer, at about 20° C., for about 2.5 hours. Suitable proteins are known to those skilled in the art and include keyhole limpet hemocyanin, bovine thyroglobulin, and ovalbumin. The same methodology may be used to conjugate proteins to carboxylic acid functionalized haptens where R¹ or R² is

Antibodies

The present invention is directed to an isolated antibody or a binding fragment thereof, which binds to olanzapine and which: (i) is generated in response to a conjugate of a compound of Formula I and an immunogenic carrier; or (ii) competes for an epitope which is the same as an epitope bound by the antibody of (i). The term “antibody” refers to a specific protein capable of binding an antigen or portion thereof (in accordance with this invention, capable of binding to an anti-psychotic drug or metabolite thereof). An antibody is produced in response to an immunogen which may have been introduced into a host, e.g., an animal or a human, by injection. The generic term “antibody” includes polyclonal antibodies, monoclonal antibodies, and antibody fragments.

“Antibody” or “antigen-binding antibody fragment” refers to an intact antibody, or a fragment thereof, that competes with the intact antibody for binding. Generally speaking, an antibody or antigen-binding antibody fragment, is said to specifically bind an antigen when the dissociation constant is less than or equal to 1 μM, preferably less than or equal to 100 nM and most preferably less than or equal to 10 nM. Binding can be measured by methods know to those skilled in the art, an example being the use of a BIAcore™ instrument.

Antibody fragments comprise a portion of an intact antibody, preferably the antigen binding or variable region of the intact antibody. Binding fragments include Fab, Fab′, F(ab′)₂, and Fv fragments; diabodies; linear antibodies; single-chain antibody molecules; and multispecific antibodies formed from antibody fragments. An antibody other than a “bispecific” or “bifunctional” antibody is understood to have each of its binding sites identical.

As used herein, “epitope” includes any protein determinant capable of specific binding to an immunoglobulin or T-cell receptor. Epitopic determinants usually consist of chemically active surface groupings of molecules such as amino acids or sugar side chains and usually have specific three dimensional structural characteristics, as well as specific charge characteristics. Two antibodies are said to “bind the same epitope” if one antibody is shown to compete with the second antibody in a competitive binding assay, by any of the methods well known to those skilled in the art (such as the BIAcore™ method referred to above). In reference to a hapten (such as olanzapine or other anti-psychotic drug), an antibody can be generated against the non-antigenic hapten molecule by conjugating the hapten to an immunogenic carrier. An antibody is then generated which recognizes an “epitope” defined by the hapten.

“Isolated” when used in the context of an antibody means altered “by the hand of man” from any natural state; i.e., that, if it occurs in nature, it has been changed or removed from its original environment, or both. For example, a naturally occurring antibody naturally present in a living animal in its natural state is not “isolated”, but the same antibody separated from the coexisting materials of its natural state is “isolated”, as the term is employed herein. Antibodies may occur in a composition, such as an immunoassay reagent, which are not naturally occurring compositions, and therein remain isolated antibodies within the meaning of that term as it is employed herein.

“Cross-reactivity” refers to the reaction of an antibody with an antigen that was not used to induce that antibody.

Preferably, the antibody of the subject invention will bind to the drug and any desired pharmacologically active metabolites. By altering the location of the attachment of the immunogenic carrier to the compounds of the invention, selectivity and cross-reactivity with metabolites can be engineered into the antibodies. For olanzapine, cross-reactivity with the related drug clozapine may or may not be desirable, and cross reactivity with olanzapine metabolites such as 10-N-gluronide or 4-N-desmethyl olanzapine may or may not be desirable. Antibodies may be generated that detect multiple ones of these drugs and/or metabolites, or antibodies may be generated that detect each separately (thus defining the antibody “specific binding” properties). An antibody specifically binds one or more compounds when its binding of the one or more compounds is equimolar or substantially equimolar.

Methods of producing such antibodies comprise inoculating a host with the conjugate described herein. Suitable hosts include, but are not limited to, mice, rats, hamsters, guinea pigs, rabbits, chickens, donkeys, horses, monkeys, chimpanzees, orangutans, gorillas, humans, and any species capable of mounting a mature immune response. The immunization procedures are well established in the art and are set forth in numerous treatises and publications including “The Immunoassay Handbook”, 2nd Edition, edited by David Wild (Nature Publishing Group, 2000) and the references cited therein.

Preferably, an immunogen embodying features of the present invention is administered to a host subject, e.g., an animal or human, in combination with an adjuvant. Suitable adjuvants include, but are not limited to, Freund's adjuvant, powdered aluminum hydroxide (alum), aluminum hydroxide together with Bordetella pertussis, and monophosphoryl lipid A-synthetic trehalose dicorynomycolate (MPL-TDM).

Typically, an immunogen or a combination of an immunogen and an adjuvant is injected into a mammalian host by one or multiple subcutaneous or intraperitoneal injections. Preferably, the immunization program is carried out over at least one week, and more preferably, over two or more weeks. Polyclonal antibodies produced in this manner can be isolated and purified utilizing methods well know in the art.

Monoclonal antibodies can be produced by the well-established hybridoma methods of Kohler and Milstein, e.g., Nature 256:495-497 (1975). Hybridoma methods typically involve immunizing a host or lymphocytes from a host, harvesting the monoclonal antibody secreting or having the potential to secrete lymphocytes, fusing the lymphocytes to immortalized cells, and selecting cells that secrete the desired monoclonal antibody.

A host can be immunized to elicit lymphocytes that produce or are capable of producing antibodies specific for an immunogen. Alternatively, the lymphocytes can be immunized in vitro. If human cells are desired, peripheral blood lymphocytes can be used, although spleen cells or lymphocytes from other mammalian sources are preferred.

The lymphocytes can be fused with an immortalized cell line to form hybridoma cells, a process which can be facilitated by the use of a fusing agent, e.g., polyethylene glycol. By way of illustration, mutant rodent, bovine, or human myeloma cells immortalized by transformation can be used. Substantially pure populations of hybridoma cells, as opposed to unfused immortalized cells, are preferred. Thus, following fusion, the cells can be grown in a suitable medium that inhibits the growth or survival of unfused, immortalized cells, for example, by using mutant myeloma cells that lack the enzyme hypoxanthine guanine phosphoribosyl transferase (HGPRT). In such an instance, hypoxanthine, aminopterin, and thymidine can be added to the medium (HAT medium) to prevent the growth of HGPRT-deficient cells while permitting hybridomas to grow.

Preferably, immortalized cells fuse efficiently, can be isolated from mixed populations by selection in a medium such as HAT, and support stable and high-level expression of antibody following fusion. Preferred immortalized cell lines include myeloma cell lines available from the American Type Culture Collection, Manassas, Va.

Because hybridoma cells typically secrete antibody extracellularly, the culture media can be assayed for the presence of monoclonal antibodies specific for the anti-psychotic drug. Immunoprecipitation of in vitro binding assays, for example, radiioimmunoassay (RIA) or enzyme-linked immunosorbent assay (ELISA), can be used to measure the binding specificity of monoclonal antibodies.

Monoclonal antibody-secreting hybridoma cells can be isolated as single clones by limiting dilution procedures and sub-cultured. Suitable culture media include, but are not limited to, Dulbecco's Modified Eagle's Medium, RPMI-1640, and polypeptide-free, polypeptide-reduced, or serum-free media, e.g., Ultra DOMA PF or HL-1, available from Biowhittaker, Walkersville, Md.. Alternatively, the hybridoma cells can be grown in vivo as ascites.

Monoclonal antibodies can be isolated and/or purified from a culture medium or ascites fluid by conventional immunoglobulin (Ig) purification procedures including, but not limited to, polypeptide A-SEPHAROSE, hydroxylapatite chromatography, gel electrophoresis, dialysis, ammonium sulfate precipitation, and affinity chromatography.

Monoclonal antibodies can also be produced by recombinant methods such as are described in U.S. Pat. No. 4,166,452. DNA encoding monoclonal antibodies can be isolated and sequenced using conventional procedures, e.g., using oligonucleotide probes that specifically bind to murine heavy and light antibody chain genes, preferably to probe DNA isolated from monoclonal antibody hybridoma cells lines secreting antibodies specific for anti-psychotic drugs.

Antibody fragments which contain specific binding sites for the anti-psychotic drug may also be generated. Such fragments include, but are not limited to, the F(ab′)₂ fragments which can be produced by pepsin digestion of the antibody molecule and the Fab fragments which can be generated by reducing the disulfide bridges of the F(ab′)₂ fragments. Alternatively, Fab expression libraries may be constructed to allow rapid and easy identification of monoclonal Fab fragments with the desired specificity (Huse et al., Science 256:1270-1281 (1989)). Fab, Fv and ScFv antibody fragments can all be expressed in and secreted from Escherichia coli, allowing for the production of large amounts of these fragments. Alternatively, Fab′-SH fragments can be directly recovered from E. coli and chemically coupled to form F(ab′)₂ fragments (Carter et al., BioTechnology 10:163-167 (1992)). Other techniques for the production of antibody fragments are known to those skilled in the art. Single chain Fv fragments (scFv) are also envisioned (see U.S. Pat. Nos. 5,761,894 and 5,587,458). Fv and sFv fragments are the only species with intact combining sites that are devoid of constant regions; thus, they are likely to show reduced non-specific binding. The antibody fragment may also be a “linear antibody” e.g., as described in U.S. Pat. No. 5,642,870, for example. Such linear antibody fragments may be monospecific or bispecific.

Assay Kits and Devices

An assay kit (also referred to as a reagent kit) can also be provided comprising an antibody as described above. A representative reagent kit may comprise an antibody that binds to the anti-psychotic drug, olanzapine, a complex comprising an analog of an anti-psychotic drug or a derivative thereof coupled to a labeling moiety, and may optionally also comprise one or more calibrators comprising a known amount of an anti-psychotic drug or a related standard.

The phrase “assay kit” refers to an assembly of materials and reagents that is used in performing an assay. The reagents can be provided in packaged combination in the same or in separate containers, depending on their cross-reactivities and stabilities, and in liquid or in lyophilized form. The amounts and proportions of reagents provided in the kit can be selected so as to provide optimum results for a particular application. An assay kit embodying features of the present invention comprises antibodies which bind olanzapine. The kit may further comprise competitive binding partners of olanzapine and calibration and control materials.

The phrase “calibration and control material” refers to any standard or reference material containing a known amount of an analyte. A sample suspected of containing an analyte and the corresponding calibration material are assayed under similar conditions. The concentration of analyte is calculated by comparing the results obtained for the unknown specimen with the results obtained for the standard. This is commonly done by constructing a calibration curve.

Antibodies embodying features of the present invention can be included in a kit, container, pack, or dispenser together with instructions for their utilization. When the antibodies are supplied in a kit, the different components of the immunoassay may be packaged in separate containers and admixed prior to use. Such packaging of the components separately may permit long-term storage without substantially diminishing the functioning of the active components. Furthermore, reagents can be packaged under inert environments, e.g., under a positive pressure of nitrogen gas, argon gas, or the like, which is especially preferred for reagents that are sensitive to air and/or moisture.

Reagents included in kits embodying features of the present invention can be supplied in all manner of containers such that the activities of the different components are substantially preserved while the components themselves are not substantially adsorbed or altered by the materials of the container. Suitable containers include, but are not limited to, ampules, bottles, test tubes, vials, flasks, syringes, envelopes, e.g., foil-lined, and the like. The containers may be comprised of any suitable material including, but not limited to, glass, organic polymers, e.g., polycarbonate, polystyrene, polyethylene, etc., ceramic, metal, e.g., aluminum, metal alloys, e.g., steel, cork, and the like. In addition, the containers may comprise one or more sterile access ports, e.g., for access via a needle, such as may be provided by a septum. Preferred materials for septa include rubber and polytetrafluoroethylene of the type sold under the trade name TEFLON by DuPont (Wilmington, Del.). In addition, the containers may comprise two or more compartments separated by partitions or membranes that can be removed to allow mixing of the components.

Reagent kits embodying features of the present invention may also be supplied with instructional materials. Instructions may be printed, e.g., on paper and/or supplied in an electronically-readable medium. Alternatively, instructions may be provided by directing a user to an internet website, e.g., specified by the manufacturer or distributor of the kit and/or via electronic mail.

The antibody may also be provided as part of an assay device. Such assay devices include lateral flow assay devices. A common type of disposable lateral flow assay device includes a zone or area for receiving the liquid sample, a conjugate zone, and a reaction zone. These assay devices are commonly known as lateral flow test strips. They employ a porous material, e.g., nitrocellulose, defining a path for fluid flow capable of supporting capillary flow. Examples include those shown in U.S. Pat. Nos. 5,559,041, 5,714,389, 5,120,643, and 6,228,660 all of which are incorporated herein by reference in their entireties.

Another type of assay device is a non-porous assay device having projections to induce capillary flow. Examples of such assay devices include the open lateral flow device as disclosed in PCT International Publication Nos. WO 2003/103835, WO 2005/089082, WO 2005/118139, and WO 2006/137785, all of which are incorporated herein by reference in their entireties.

In a non-porous assay device, the assay device generally has at least one sample addition zone, at least one conjugate zone, at least one reaction zone, and at least one wicking zone. The zones form a flow path by which sample flows from the sample addition zone to the wicking zone. Also included are capture elements, such as antibodies, in the reaction zone, capable of binding to the analyte, optionally deposited on the device (such as by coating); and a labeled conjugate material also capable of participating in reactions that will enable determination of the concentration of the analyte, deposited on the device in the conjugate zone, wherein the labeled conjugate material carries a label for detection in the reaction zone. The conjugate material is dissolved as the sample flows through the conjugate zone forming a conjugate plume of dissolved labeled conjugate material and sample that flows downstream to the reaction zone. As the conjugate plume flows into the reaction zone, the conjugated material will be captured by the capture elements such as via a complex of conjugated material and analyte (as in a “sandwich” assay) or directly (as in a “competitive” assay). Unbound dissolved conjugate material will be swept past the reaction zone into the at least one wicking zone. Such devices can include projections or micropillars in the flow path.

An instrument such as that disclosed in US Patent Publication Nos. US20060289787A1 and US 20070231883A1, and U.S. Pat. Nos. 7,416,700 and 6,139,800, all of which are incorporated herein by reference in their entireties, is able to detect the bound conjugated material in the reaction zone. Common labels include fluorescent dyes that can be detected by instruments which excite the fluorescent dyes and incorporate a detector capable of detecting the fluorescent dyes.

Immunoassays

The antibodies thus produced can be used in immunoassays to recognize/bind to the anti-psychotic drug, thereby detecting the presence and/or amount of the drug in a patient sample. Preferably, the assay format is a competitive immunoassay format. Such an assay format and other assays are described, among other places, in Hampton et al. (Serological Methods, A Laboratory Manual, APS Press, St. Paul, Minn. 1990) and Maddox et al. (J. Exp. Med. 158:12111, 1983).

The term “analyte” refers to any substance or group of substances, the presence or amount of which is to be determined. Representative anti-psychotic drug analytes include, but are not limited to, risperidone, paliperidone, olanzapine, aripiprazole, and quetiapine.

The term “competitive binding partner” refers to a substance or group of substances, such as may be employed in a competitive immunoassay, which behave similarly to an analyte with respect to binding affinity to an antibody. Representative competitive binding partners include, but are not limited to, anti-psychotic drug derivatives and the like.

The term “detecting” when used with an analyte refers to any quantitative, semi-quantitative, or qualitative method as well as to all other methods for determining an analyte in general, and an anti-psychotic drug in particular. For example, a method that merely detects the presence or absence of an anti-psychotic drug in a sample lies within the scope of the present invention, as do methods that provide data as to the amount or concentration of the anti-psychotic drug in the sample. The terms “detecting”, “determining”, “identifying”, and the like are used synonymously herein, and all lie within the scope of the present invention.

A preferred embodiment of the subject invention is a competitive immunoassay wherein antibodies which bind the anti-psychotic drug, or the drug or competitive binding partner thereof, are attached to a solid support (such as the reaction zone in a lateral flow assay device) and labeled drug or competitive binding partner thereof, or labeled antibody, respectively, and a sample derived from the host are passed over the solid support and the amount of label detected attached to the solid support can be correlated to a quantity of drug in the sample.

Any sample that is suspected of containing an analyte, e.g., an anti-psychotic drug, can be analyzed in accordance with the methods of the presently preferred embodiments. The sample can be pretreated if desired and can be prepared in any convenient medium that does not interfere with the assay. Preferably, the sample comprises an aqueous medium such as a body fluid from a host, most preferably plasma or serum.

It is to be understood that all manner of immunoassays employing antibodies are contemplated for use in accordance with the presently preferred embodiments, including assays in which antibodies are bound to solid phases and assays in which antibodies are in liquid media. Methods of immunoassays that can be used to detect analytes using antibodies embodying features of the present invention include, but are not limited to, competitive (reagent limited) assays wherein labeled analyte (analyte analog) and analyte in a sample compete for antibodies and single-site immunometric assays wherein the antibody is labeled; and the like.

The present invention is further described by the following examples. The examples are provided solely to illustrate the invention by reference to specific embodiments. These exemplifications, while illustrating certain specific aspects of the invention, do not portray the limitations or circumscribe the scope of the disclosed invention.

All examples were carried out using standard techniques, which are well known and routine to those of skill in the art, except where otherwise described in detail. Routine molecular biology techniques of the following examples can be carried out as described in standard laboratory manuals, such as Sambrook et al., Molecular Cloning: A Laboratory Manual, 2nd Ed., Cold Spring Harbor Laboratory Press, Cold Spring Harbor, N.Y. (1989).

Copending applications entitled “Haptens of Aripiprazole” (U.S. Provisional Patent Appl. No. 61/691,450, filed Aug. 21, 2012, and US 20140163206, filed Aug. 20, 2013), “Haptens of Olanzapine” (U.S. Provisional Patent Appl. No. 61/691,454, filed Aug. 21, 2012, and US 20140213766, filed Aug. 20, 2013), “Haptens of Paliperidone” (U.S. Provisional Patent Appl. No. 61/691,459, filed Aug. 21, 2012, and US 20140213767, filed Aug. 20, 2013), “Haptens of Quetiapine” (U.S. Provisional Patent Appl. No. 61/691,462, filed Aug. 21, 2012, and US 20140221616, filed Aug. 20, 2013), “Haptens of Risperidone and Paliperidone” (U.S. Provisional Patent Appl. No. 61/691,469, filed Aug. 21, 2012, and US 20140155585, Aug. 20, 2013), “Antibodies to Aripiprazole Haptens and Use Thereof” (U.S. Provisional Patent Appl. No. 61/691,544, filed Aug. 21, 2012, and US 20140057299, filed Aug. 20, 2013), “Antibodies to Paliperidone Haptens and Use Thereof” (U.S. Provisional Patent Appl. No. 61/691,634, filed Aug. 21, 2012, and US 20140057297, filed Aug. 20, 2013), “Antibodies to Quetiapine Haptens and Use Thereof” (U.S. Provisional Patent Appl. No. 61/691,598, filed Aug. 21, 2012, and US 20140057305, filed Aug. 20, 2013), “Antibodies to Risperidone Haptens and Use Thereof” (U.S. Provisional Patent Appl. No. 61/691,615, filed Aug. 21, 2012, and US 20140057301, filed Aug. 20, 2013), “Antibodies to Aripiprazole and Use Thereof” (U.S. Provisional Patent Appl. No. 61/691,522, filed Aug. 21, 2012, and US 20140057300, filed Aug. 20, 2013), “Antibodies to Olanzapine and Use Thereof” (U.S. Provisional Patent Appl. No. 61/691,645, filed Aug. 21, 2012, and US 20140057304, filed Aug. 20, 2013), “Antibodies to Paliperidone and Use Thereof” (U.S. Provisional Patent Appl. No. 61/691,692, filed Aug. 21, 2012, and US 20140057298, filed Aug. 20, 2013), “Antibodies to Quetiapine and Use Thereof” (U.S. Provisional Patent Appl. No. 61/691,659, filed Aug. 21, 2012, and US 20140057306, filed Aug. 20, 2013), “Antibodies to Risperidone and Use Thereof” (U.S. Provisional Patent Appl. No. 61/691,675, filed Aug. 21, 2012, and US 20140057302, filed Aug. 20, 2013), and “Antibodies to Risperidone and Use Thereof” (U.S. Provisional Patent Appl. No. 61/790,880, filed Mar. 15, 2013, and US 20140057302, filed Aug. 20, 2013) are all incorporated herein by reference in their entireties.

Example 1 (1-Methyl-4-(2-methyl-10H-benzo[b]thieno[2,3-e][1,4]diazepin-4-yl)piperazin-2-yl)methanamine

Step A tert-Butyl 3-cyanopiperazine-1-carboxylate

To a solution of tert-butyl 3-cyanopiperazine-1-carboxylate (21.1 g, 0.1 mol) and aqueous formaldehyde (24 g, 37% in water) in THF was added sodium cyanoborohydride (31.5 g, 0.5 mol) in small portions. The reaction mixture was aged at ambient temperature overnight then diluted with water and extracted with ethyl acetate. The organic phase was washed with saturated aqueous sodium chloride, dried over anhydrous sodium sulfate, filtered, and concentrated under vacuum. The crude product was purified by column chromatography to provide the title compound. ¹H NMR (400 MHz, MeOD) δ4.23-4.18 (m, 1H), 4.01-3.97 (br, 1H), 3.92-3.90 (br, 1H), 2.92-2.89 (br, 1H), 2.88-2.87 (br, 1H), 2.65-2.62 (m, 1H), 2.378 (s, 3H), 2.36-2.33 (m, 1H), 1.47 (s, 9H).

Step B tert-Butyl 3-(aminomethyl)-4-methylpiperazine-1-carboxylate

To a solution of tert-butyl 3-cyano-4-methylpiperazine-1-carboxylate, prepared as described in Step A, (10.5 g, 47 mmol) in methanol (200 mL) was added metallic nickel (10 g) and triethylamine (5 mL). The mixture was stirred at ambient temperature overnight under atmosphere of hydrogen gas (50 psi). Upon consumption of tert-butyl 3-cyano-4-methylpiperazine-1-carboxylate, the mixture was filtered, and the filtrate was concentrated under vacuum to provide crude tert-butyl 3-(aminomethyl)-4-methylpiperazine-1-carboxylate used in the next step without purification.

Step C tert-Butyl 3-((1,3-dioxoisoindolin-2-yl)methyl)-4-methylpiperazine-1-carboxylate

To a mixture of tert-butyl 3-(aminomethyl)-4-methylpiperazine-1-carboxylate, prepared as described in the previous step, (5.5 g, crude) and sodium bicarbonate (2.52 g, 30 mmol) in tetrahydrofuran (100 mL) was added a solution of 2H-isoindole-2-carboxylic acid, 1,3-dihydro-1,3-dioxo-, ethyl ester (6.59 g, 30 mmol) in tetrahydrofuran (20 mL) at ambient temperature. After stirring for 30 minutes, the suspension was filtered, and the filtrate was concentrated to give crude product which was purified by column chromatography to provide the title compound. ¹H NMR (400 MHz, MeOD) δ7.87-7.85 (m, 2H), 7.87-7.80 (m, 2H), 3.94-3.90 (m, 1H), 3.75-3.65 (br, 3H), 3.43-3.41 (br, 1H), 3.30-3.28 (m, 2H), 3.49 (s, 3H), 2.39-2.38 (m, 1H), 2.30-2.28 (m, 1H), 1.36 (s, 9H).

Step D 2-((1-Methylpiperazin-2-yl)methyl)isoindoline-1,3-dione

A solution of tert-butyl 3-((1,3-dioxoisoindolin-2-yl)methyl)-4-methylpiperazine-1-carboxylate, prepared as described in the previous step, (8.6 g) in methanolic hydrogen chloride (20 mL) was stirred at room temperature for 1 hour. The solvent was removed under vacuum to provide 2-((1-methylpiperazin-2-yl)methyl)isoindoline-1,3-dione which was used in the next step without further purification. ¹H NMR (400 MHz, MeOD) δ7.88-7.86 (m, 2H), 7.82-7.80 (m, 2H), 3.99-3.95 (m, 1H), 3.77-3.73 (m, 1H), 3.24-3.23 (m, 1H), 3.29-3.23 (m, 1H), 3.17-3.14 (m, 1H), 3.04-2.84 (m, 2H), 2.81-2.78 (m, 1H), 2.55 (s, 3H), 2.46-2.40 (m, 1H).

Step E 5-Methyl-2-((2-nitrophenyl)amino)thiophene-3-carbonitrile

To a solution of 2-amino-5-methylthiophene-3-carbonitrile (13.8 g, 100 mmol) and 1-fluoro-2-nitrobenzene (16.92 g, 120 mmol) in dimethylsulfoxide was added potassium hydroxide (11.2 g, 200 mmol). The reaction mixture was stirred at room temperature overnight. The mixture was diluted with water, and the resulting suspension was filtered. The filtered cake was dried to give 5-methyl-2-((2-nitrophenyl)amino)thiophene-3-carbonitrile as a red solid used without further purification. ¹H NMR: (400 MHz, CDCl₃) δ9.69 (s, 1H), 8.27-8.25 (m, 1H), 7.56-7.52 (m, 1H), 7.23-7.20 (m, 1H), 7.0-6.96 (m, 1H), 6.80 (s, 1H), 2.49 (s, 3H).

Step F 2-((2-Aminophenyl)amino)-5-methylthiophene-3-carbonitrile

To a solution of 5-methyl-2-((2-nitrophenyl)amino)thiophene-3-carbonitrile, prepared as described in the previous step, (43.3 g, 0.157 mol) in ethyl acetate (500 mL) was added 10% palladium on carbon (8 g). The black mixture was stirred at room temperature overnight under an atmosphere of hydrogen gas. When LCMS showed that most of 5-methyl-2-((2-nitrophenyl)amino)thiophene-3-carbonitrile was consumed completely, the mixture was filtered and the filtrate was concentrated to provide 2-((2-aminophenyl)amino)-5-methylthiophene-3-carbonitrile. ¹H NMR (400 MHz, CDCl₃) δ7.29-7.21 (m, 1H), 7.11-7.10 (m, 1H), 6.86-6.79 (m, 2H), 6.48-6.47 (m, 1H), 6.42 (brs, 1H), 3.75-3.70 (br, 2H), 2.28 (s, 3H).

Step G 2-Methyl-10H-benzo[b]thieno[2,3-e][1,4]diazepin-4-amine

A mixture of 2-((2-aminophenyl)amino)-5-methylthiophene-3-carbonitrile, prepared as described in the previous step, (22.9 g, 100 mmol) in isopropanol (150 mL) and aqueous hydrochloric acid (50 mL, 18%) was heated at 80° C. for 3 hrs. The resulting suspension was filtered and the filter cake was dried to give the title compound as a red solid. ¹H NMR (400 MHz CDCl₃) δ7.14-7.12 (t, 1H), 7.7.12-7.10 (t, 1H), 6.95-6.93 (d, J=8 MHz, 1H), 6.81-6.79 (d, J=8 MHz, 1H), 6.70 (s, 1H), 2.30 (s, 3H).

Step H 2-((1-Methyl-4-(2-methyl-10H-benzo[b]thieno[2,3-e][1,4]diazepin-4-yl)piperazin-2-yl)methyl)isoindoline-1,3-dione

A solution of 2-((1-methylpiperazin-2-yl)methyl)isoindoline-1,3-dione, prepared as described in step D, (100 mg, 0.38 mmol), 2-methyl-10H-benzo[b]thieno[2,3-e][1,4]diazepin-4-amine, prepared as described in step G, (150 mg, 0.52 mmol) and diisopropylethylamine (0.49 g, 3.8 mmol) in dimethylsulfoxide (0.5 mL) was stirred at 170° C. for 2 hrs. The reaction was diluted with water and extracted with ethyl acetate. The organic phase was concentrated and the residue purified by column to give 15 mg of 2-((1-methyl-4-(2-methyl-10H-benzo[b]thieno[2,3-e][1,4]diazepin-4-yl)piperazin-2-yl)methyl)isoindoline-1,3-dione. ¹H NMR (400 MHz, CDCl₃) δ7.76-7.73 (m, 1H), 7.45-7.35 (m, 3H), 7.18-7.17 (m, 1H), 6.98-6.95 (m, 2H), 6.75-6.73 (m, 1H), 6.46 (s, 1H), 4.28-4.25 (m, 1H), 3.96-6.92 (m, 1H), 3.71-3.64 (m, 3H), 3.47-3.41 (m, 1H), 3.29-3.28 (m, 1H), 3.12-3.09 (m, 1H), 2.87-2.86 (m, 1H), 2.67-2.53 (m, 3H), 2.28 (s, 3H).

Step I (1-Methyl-4-(2-methyl-10H-benzo[b]thieno[2,3-e][1,4]diazepin-4-yl)piperazin-2-yl)methanamine

A solution of 2-((1-methyl-4-(2-methyl-10H-benzo[b]thieno[2,3-e][1,4]diazepin-4-yl)piperazin-2-yl)methyl)isoindoline-1,3-dione, prepared as described in the previous step, (1.0 g) in ethanolic methylamine (20 mL) was stirred at ambient temperature overnight. The solvent was removed under vacuum and the residue purified by HPLC to give the hydrochloride salt of (1-methyl-4-(2-methyl-10H-benzo[b]thieno[2,3-e][1,4]diazepin-4-yl)piperazin-2-yl)methanamine as a red solid. ¹H NMR (400 MHz, MeOD) δ7.46-7.44 (m, 1H), 7.31-7.48 (m, 1H), 7.19-7.15 (m, 1H), 6.97-6.95 (m, 1H), 6.74 (s, 1H), 4.80-4.71 (br, 1H), 4.28-4.20 (br, 2H), 4.07-4.04 (br, 2H), 3.82-3.70 (br, 3H), 3.53-3.48 (m, 1H), 3.18 (s, 3H), 2.42 (m, 3H); ESI-MS (M+1): 342 calc. for C18H23N5S Exact Mass: 341.17.

Example 2 2-(2,5-Dioxo-2,5-dihydro-1H-pyrrol-1-yl)-N-((1-methyl-4-(2-methyl-10H-benzo[b]thieno[2,3-e][1,4]diazepin-4-yl)piperazin-2-yl)methyl)acetamide

To a solution of (1-methyl-4-(2-methyl-10H-benzo[b]thieno[2,3-e][1,4]diazepin-4-yl)piperazin-2-yl)methanamine, prepared as described in Example 1, (10.3 mg, 30.2 μmoles) in 570 μL of DMF and 13.3 μL of tributylamine was added 760 μL of a DMF solution of N-(α-maleimidoacetoxy) succinimide ester (AMAS, 10 mg/mL, 7.6 mg, 30.2 μmoles). The resulting solution was allowed to stir for 18 hours at 20° C., then used as such in conjugation reactions with thiol-activated protein.

Example 3 (2-Methyl-4-(4-methylpiperazin-1-yl)-10H-benzo[b]thieno[2,3-e][1,4]diazepin-7-yl)methanamine

Step A 2-(4-Cyano-2-nitro-phenylamino)-5-methyl-thiophene-3-carbonitrile

To a suspension of sodium hydride (60%, 0.58 g) in THF (2 mL), was added 4-fluoro-3-nitro-benzonitrile (1.33 g, 8.0 mmol) and 2-amino-5-methyl-thiophene-3-carbonitrile (1.10 g, 8.0 mmol) in THF (10 mL), dropwise. The mixture was stirred at room temperature overnight. Two more batches of sodium hydride (60%, 0.50 g and 0.4 g) were added over the next 6 hours. After stirring for 3 days, the mixture was poured into ice-water (20 mL) and acidified to pH 3 with 6N hydrochloric acid (7 mL). The precipitate was filtered and washed with water. The solid was extracted with dichloromethane (35 mL). The solution was concentrated to a solid, and used in the next step without additional purification. LC-MS: m/z 285 (M+1), 307 (M+23). ¹H NMR (CDCl₃, 400 MHz): δ (ppm) 9.76 (s, 1H), 8.59 (s, 1H), 7.70 (d, 1H), 7.14 (d, 1H), 6.87 (s, 1H), 2.52 (s, 1H).

Step B 10-Amino-2-methyl-4H-3-thia-4,9-diaza-benzo[f]azulene-7-carbonitrile hydrochloride

To a suspension of 2-(4-Cyano-2-nitro-phenylamino)-5-methyl-thiophene-3-carbonitrile, prepared as described in the previous step, (0.52 g) in ethanol (5 mL), was added tine chloride (1.36 g, 7.2 mmol) in 6 N HCl. The mixture was heated in an 85° C. oil bath for 3 hours and then cooled in ice bath. The solid was filtered, washed with water, and dried to brown give the title compound as a brown solid containing inorganic salt, which was used in the next step without additional purification. LC-MS: m/z 255 (M+1 of free base). ¹H NMR (DMSO-d₆, 400 MHz): δ (ppm) 11.18 (br, 1H), 10.09 (s, 1H), 9.35 (br, 1H), 8.94 (br, 1H), 7.54 (d, 1H), 7.27 (s, 1H), 6.95 (d, 1H), 2.26 (s, 3H).

Step C 2-Methyl-10-(4-methyl-piperazin-1-yl)-4H-3-thia-4,9-diaza-benzo[f]azulene-7-carbonitrile

To a solution of 10-amino-2-methyl-4H-3-thia-4,9-diaza-benzo[f]azulene-7-carbonitrile hydrochloride, prepared as described in the previous step, (0.6 g) in DMSO (6 mL) and toluene (6 mL), was added 1-methylpiperazine (4 mL). The mixture was heated in a 130° C. oil bath for 17 hours. The solution was concentrated, diluted with ethyl acetate (50 mL), washed with water (20 mL) and brine (20 mL), and then concentrated. The solid was dissolved in dichloromethane (10 mL) and treated with saturated sodium bicarbonate solution. The title compound was collected as a light yellow precipitate, washed with water and dichloromethane, dried, and used in the next step without additional purification. LC-MS: m/z 338 (M+1). ¹H NMR (CD₃OD, 400 MHz): δ (ppm) 7.19-7.15 (m, 2H), 6.74 (d, 1H), 6.37 (s, 1H), 3.51 (m, 4H), 2.53 (m, 4H), 2.34 (s, 3H), 2.32 (s, 3H).

Step D (2-Methyl-4-(4-methylpiperazin-1-yl)-10H-benzo[b]thieno[2,3-e][1,4]diazepin-7-yl)methanamine

To a solution of 2-Methyl-10-(4-methyl-piperazin-1-yl)-4H-3-thia-4,9-diaza-benzo[f]azulene-7-carbonitrile, prepared as described in the previous step, (0.25 g) in methanol (90 mL) was added concentrated HCl (0.4 mL) and Pd black (57 mg). Hydrogenation was carried out at 50 psi for 1 h. More Pd black (147 mg) was added. The mixture was shaken at 50 psi for 22 h. The catalyst was filtered and washed with methanol. The filtrate was concentrated, treated with saturated sodium bicarbonate solution (5 mL), and concentrated to dryness. The product was purified by silica column. LC-MS: m/z 342 (M+1). ¹H NMR (CD₃OD, 400 MHz): δ (ppm) 6.89-6.85 (m, 2H), 6.64 (d, 1H), 6.34 (d, 1H), 3.66 (s, 2H), 3.46 (m, 4H), 2.54 (m, 4H), 2.34 (s, 3H), 2.30 (d, 3H).

Example 4 2-(2,5-Dioxo-2,5-dihydro-1H-pyrrol-1-yl)-N-((2-methyl-4-(4-methylpiperazin-1-yl)-10H-benzo[b]thieno[2,3-e][1,4]diazepin-7-yl)methyl)acetamide

To a solution of (2-methyl-4-(4-methylpiperazin-1-yl)-10H-benzo[b]thieno[2,3-e][1,4]diazepin-7-yl)methanamine, prepared as described in Example 3, (3.5 mg, 10.2 μmoles) in 185 μL of DMF and 4.5 μL of tributylamine was added 260 μL of a DMF solution of N-(α-maleimidoacetoxy) succinimide ester (AMAS, 10 mg/mL, 2.6 mg, 10.2 μmoles). The resulting solution was allowed to stir for 90 minutes at 20° C., then used as such in conjugation reaction with thiol-activated protein.

Example 5 6-(2,5-dioxo-2,5-dihydro-1H-pyrrol-1-yl)-N-((2-methyl-4-(4-methylpiperazin-1-yl)-10H-benzo[b]thieno[2,3-e][1,4]diazepin-7-yl)methyl)hexanamide

To a solution of (2-methyl-4-(4-methylpiperazin-1-yl)-10H-benzo[b]thieno[2,3-e][1,4]diazepin-7-yl)methanamine, prepared as described in Example 3, (59 mg, 0.17 mmol) in dichloromethane (4 mL) was added triethylamine (0.048 mL, 0.34 mmol) and 6-maleimidohexanoic N-hydroxysuccinimide ester (53 mg, 0.17 mmol) in dichloromethane (1 mL). The solution was stirred at room temperature for 40 min, then loaded onto a silica column, eluted with 3-5% methanol/dichloromethane containing triethylamine. The title compound was obtained as a yellow solid. LC-MS: m/z 535 (M+1).

Example 6 N-[2-Methyl-10-(4-methyl-piperazin-1-yl)-4H-3-thia-4,9-diaza-benzo[f]azulen-7-ylmethyl]-succinamic Acid

Step A Succinic Acid 2,5-dioxo-pyrrolidin-1-yl Ester Methyl Ester

To a solution of 1-hydroxy-pyrrolidine-2,5-dione (1.23 mL, 10 mmol) in ethyl acetate (50 mL) was added 3-chlorocarbonyl-propionic acid methyl ester (1.15 g, 10 mmol). The mixture was cooled in an ice bath. Triethylamine (1.4 mL, 10 mmol) was added dropwise. The resulting suspension was stirred for 10 min in an ice bath and for 5 min without ice bath. The white solid was removed by filtration and washed with ethyl acetate (3×3 mL). The filtrate was concentrated to a white solid (2.32 g).

Step B N-[2-Methyl-10-(4-methyl-piperazin-1-yl)-4H-3-thia-4,9-diaza-benzo[f]azulen-7-ylmethyl]-succinamic Acid Methyl Ester

To a solution of (2-methyl-4-(4-methylpiperazin-1-yl)-10H-benzo[b]thieno[2,3-e][1,4]diazepin-7-yl)methanamine, prepared as described in Example 3, (40 mg, 0.12 mmol) in dichloromethane (2 mL) was added triethylamine (0.030 mL, 0.22 mmol) and succinic acid 2,5-dioxo-pyrrolidin-1-yl ester methyl ester, prepared as described in the previous step, (31 mg, 0.13 mmol). The solution was stirred at room temperature for 1 hour and concentrated. The crude was loaded onto a silica column, eluted with 3-5% methanol/dichloromethane containing ammonium hydroxide to give the title compound as a yellow solid. LC-MS: m/z 456 (M+1).

Step C N-[2-Methyl-10-(4-methyl-piperazin-1-yl)-4H-3-thia-4,9-diaza-benzo[f]azulen-7-ylmethyl]-succinamic Acid

To a suspension of N-[2-methyl-10-(4-methyl-piperazin-1-yl)-4H-3-thia-4,9-diaza-benzo[f]azulen-7-ylmethyl]-succinamic acid methyl ester, prepared as described in the previous step, (80 mg, 0.18 mmol) in THF (1.5 mL) was added LiOH (14 mg) in water (0.5 mL). The solution was stirred at room temperature for 3 h, acidified with dilute HCl, and concentrated to dryness. LC-MS: m/z 442 (M+1 of the parent).

Example 7 2-(2,5-dioxo-2,5-dihydro-1H-pyrrol-1-yl)-N-((1-methyl-4-(2-methyl-10H-benzo[b]thieno[2,3-e][1,4]diazepin-4-yl)piperazin-2-yl)methyl)acetamide-keyhole Limpet Hemocyanin-Conjugate Step A

To a 3.19 mL solution of keyhole limpet hemocyanin (KLH, 15.2 mg, 0.152 μmoles) in 100 mM phosphate buffer, 0.46M sodium chloride, at pH 7.4 was added 70.3 μL of a DMF solution of N-succinimidyl-S-acetylthioacetate (SATA, 25 mg/mL, 1.75 mg, 7.60 μmoles). The resulting solution was incubated at 20° C. for 1 hour on a roller mixer. To the reaction was added 319 μL of 2.5M hydroxylamine, 50 mM EDTA, pH 7.0 and the resulting solution was incubated at 20° C. for 25 min, on a roller mixer. The reaction was purified on a Sephadex G-25 column using 100 mM phosphate buffer, 0.46 M sodium chloride, 5 mM EDTA, at pH 6.0.

Step B

To the KLH-SH, prepared as described in the previous step, (4.29 mL, 12.7 mg 0.127 μmoles) was added an aliquot of the solution prepared in Example 2, (566.6 μL, 12.7 μmoles). The resulting cloudy mixture was incubated for 2 hours at 20° C. on a roller mixer. The reaction was filtered through a 20 μm syringe filter then purified on a Sephadex G-25 column using 100 mM phosphate buffer, 0.46 M sodium chloride, at pH 7.4.

Example 8 2-(2,5-dioxo-2,5-dihydro-1H-pyrrol-1-yl)-N-((1-methyl-4-(2-methyl-10H-benzo[b]thieno[2,3-e][1,4]diazepin-4-yl)piperazin-2-yl)methyl)acetamide-bovine Thyroglobulin-Conjugate Step A

To 2.0 mL of a solution of bovine thyroglobulin (BTG, 20.0 mg, 0.03 μmoles) in 100 mM phosphate buffer pH 7.5 was added 276.0 μL of a DMF solution of N-succinimidyl-S-acetylthioacetate (SATA, 25 mg/mL, 6.9 mg, 30.0 μmoles). The resulting solution was incubated at 20° C. for 1 hour on a roller mixer. To the reaction was added 230 μL of 2.5 M hydroxylamine, 50 mM EDTA, pH 7.0. The resulting solution was incubated at 20° C. for 15 minutes on a roller mixer. The reaction was purified on a Sephadex G-25 column using 100 mM phosphate buffer, 5 mM EDTA, at pH 6.0.

Step B

To the BTG-SH, prepared as described in the previous step, (4.73 mL, 14.3 mg, 0.022 μmoles) was added an aliquot of the solution prepared in Example 2, (969.6 μL, 21.7 μmoles). The resulting cloudy mixture was incubated for 3 hours at 20° C. on a roller mixer. The reaction was filtered through a 0.45 μm syringe filter, then purified on a Sephadex G-25 column using 100 mM phosphate buffer, 0.14M sodium chloride, at pH 7.4.

Example 9 2-(2,5-dioxo-2,5-dihydro-1H-pyrrol-1-yl)-N-((1-methyl-4-(2-methyl-10H-benzo[b]thieno[2,3-e][1,4]diazepin-4-yl)piperazin-2-yl)methyl)acetamide-ovalbumin-conjugate Step A

To 1.2 mL of a solution of ovalbumin (12.0 mg, 0.27 μmoles) in 100 mM phosphate buffer pH 7.5 was added 50.1 μL of a DMF solution of N-succinimidyl-S-acetylthioacetate (SATA, 25 mg/mL, 1.25 mg, 5.42 μmoles). The resulting solution was incubated at 20° C. for 1 hour on a roller mixer. To the reaction was added 120 μL of 2.5M hydroxylamine, 50 mM EDTA, at pH 7.0. The resulting solution was incubated at 20° C. for 15 minutes on a roller mixer. The reaction was purified on a Sephadex G-25 column using 100 mM phosphate buffer, 5 mM EDTA, at pH 6.0.

Step B

To the ovalbumin-SH, prepared as described in the previous step, (4.2 mL, 8.0 mg, 0.18 μmoles) was added an aliquot of the solution prepared in Example 2, (200 μL, 4.5 μmoles). The resulting mixture was incubated for 3 hours at 20° C. on a roller mixer. The reaction was purified on a Sephadex G-25 column using 100 mM phosphate buffer, 0.14M sodium chloride, at pH 7.4.

Example 10 2-(2,5-dioxo-2,5-dihydro-1H-pyrrol-1-yl)-N-((2-methyl-4-(4-methylpiperazin-1-yl)-10H-benzo[b]thieno[2,3-e][1,4]diazepin-7-yl)methyl)acetamide—Keyhole Limpet Hemocyanin—Conjugate

To the KLH-SH, prepared as described in Example 7 Step A, (3.31 mL, 9.8 mg, 0.098 μmoles) was added a 300 μL aliquot of 2-(2,5-dioxo-2,5-dihydro-1H-pyrrol-1-yl)-N-((2-methyl-4-(4-methylpiperazin-1-yl)-10H-benzo[b]thieno[2,3-e][1,4]diazepin-7-yl)methyl)acetamide solution, prepared as described in Example 4, (6.9 μmoles). The resulting cloudy mixture was incubated for 2.5 hours at 20° C. on a roller mixer. The reaction was filtered through a 0.2 μm syringe filter then purified on a Sephadex G-25 column using 100 mM phosphate buffer, 0.46 M sodium chloride, at pH 7.4.

Example 11 2-(2,5-dioxo-2,5-dihydro-1H-pyrrol-1-yl)-N-((2-methyl-4-(4-methylpiperazin-1-yl)-10H-benzo[b]thieno[2,3-e][1,4]diazepin-7-yl)methyl)acetamide-ovalbumin-conjugate

To the ovalbumin-SH, prepared as described in Example 9 Step A, (5.38 mL, 17.8 mg, 0.40 μmoles) was added a 200 μL aliquot of 2-(2,5-dioxo-2,5-dihydro-1H-pyrrol-1-yl)-N-((2-methyl-4-(4-methylpiperazin-1-yl)-10H-benzo[b]thieno[2,3-e][1,4]diazepin-7-yl)methyl)acetamide solution, prepared as described in Example 4, (10.2 μmoles). The resulting mixture was incubated for 3 hours at 20° C. on a roller mixer. The reaction was filtered through a 0.45 μm syringe filter then purified on a Sephadex G-25 column using 100 mM phosphate buffer, 0.14 M sodium chloride, at pH 7.4.

Example 12 N-[2-Methyl-10-(4-methyl-piperazin-1-yl)-4H-3-thia-4,9-diaza-benzo[f]azulen-7-ylmethyl]-succinamic Acid-Bovine Thyroglobulin-Conjugate Step A

A solution of N-[2-Methyl-10-(4-methyl-piperazin-1-yl)-4H-3-thia-4,9-diaza-benzo[f]azulen-7-ylmethyl]-succinamic acid, prepared as described in Example 6, (7.9 mg, 18.0 μmoles), N-hydroxysuccinimide (NHS, 8.3 mg, 72.0 μmoles) and N,N-dicyclohexylcarbodiimide (14.9 mg, 72.0 μmoles) in 500 μL of DMF and 5 μL of tributylamine was allowed to stir for 18 hours at 20° C., then used as such in conjugation with protein.

Step B

To 2.98 mL of a solution of bovine thyroglobulin (BTG, 14.9 mg, 0.023 μmoles) in 100 mM phosphate buffer pH 7.5 was added 500 μL of the solution prepared in Step A (18.0 μmoles). The resulting cloudy mixture was incubated at 20° C. for 2.5 hours on a roller mixer. The reaction was filtered through a 0.45 μm syringe filter then purified on a Sephadex G-25 column using 100 mM phosphate buffer, 0.14 M sodium chloride, at pH 7.4.

Example 13 Competitive Immunoassays for Olanzapine and Multiplex Competitive Immunoassay for Aripiprazole, Olanzapine, Quetiapine, and Risperidone/Paliperidone

Following a series of immunizations with olanzapine immunogens having Formulas II and III, mouse tail bleeds were tested for reactivity using an ELISA. Hybridoma supernatants were also tested, and the ELISA data shown in Tables 8 (hybridomas generated against an olanzapine immunogen having Formula II) and 9 (hybridomas generated against an olanzapine immunogen having Formula III) below shows reactivity of several hybridomas (fusion partner was NSO cells).

TABLE 8 Plate 2 Dilution 1 2 3 4 5 6 7 8  1/400 25 26 27 28 29 30 31 21  1/1200  1/3600 1/10800  1/400 37 38 39 40 41 42 43 44  1/1200  1/3600 1/10800  1/400 0.0136 0.0432 0.131 0.0654 0.4092 0.039 0.016 0.1408  1/1200 0.0113 0.0194 0.0477 0.0291 0.1293 0.031 0.012 0.0374  1/3600 0.0092 0.0118 0.0233 0.0153 0.0462 0.013 0.009 0.0314 1/10800 0.0105 0.0111 0.0159 0.0107 0.0224 0.012 0.009 0.0172  1/400 0.0333 0.1512 1.1412 1.0762 0.3042 0.04 0.449 0.1619  1/1200 0.0144 0.055 0.4575 0.3223 0.0907 0.016 0.144 0.0402  1/3600 0.008 0.0333 0.2036 0.1077 0.0361 0.011 0.051 0.0206 1/10800 0.0109 0.0181 0.0885 0.0581 0.027 0.01 0.045 0.0217 Dilution 9 10 11 12  1/400 33 34 35 36 Ag =  1/1200 Bt-Com-  1/3600 pound 1/10800 #11  1/400 45 46 47 48  1/1200  1/3600 1/10800  1/400 0.0712 1.4854 2.0086 0.0861  1/1200 0.0126 0.4411 0.8874 0.0362  1/3600 0.0275 0.2073 0.3555 0.0217 1/10800 0.0168 0.0972 0.147 0.0141  1/400 1.8038 0.0933 0.7666 1.258  1/1200 0.1536 0.0288 0.2956 0.4374  1/3600 0.708 0.0165 0.1212 0.2072 1/10800 0.5338 0.0132 0.0585 0.0954

TABLE 9 Plate 3 Dilution 1 2 3 4 5 6 7 8 100 1B2 1C4 2B3 2G5 3A3 3E9 3F11 4G9 100 300 300 900 900 2700 2700 100 0.0628 0.5634 2.9908 1.9083 0.7869 2.7554 2.296 1.027 100 0.0527 0.429 2.7862 1.3797 0.6534 2.3072 2.0249 0.934 300 0.0202 0.1452 1.3705 0.5961 0.2337 1.3963 0.8952 0.2999 300 0.0208 0.1408 1.3166 0.5235 0.2173 1.1112 0.9114 0.3116 900 0.0132 0.0242 0.4925 0.1967 0.0849 0.4472 0.2986 0.0896 900 0.0148 0.0554 0.4551 0.1731 0.0839 0.4471 0.3499 0.0951 2700 0.0109 0.0259 0.1877 0.0713 0.0334 0.1709 0.1381 0.0352 2700 0.0122 0.028 0.1835 0.0903 0.0404 0.1924 0.1502 0.0409 Dilution 9 10 11 12 100 5D11 6G2 #13 Empty 100 300 300 900 900 2700 2700 100 0.1174 0.8223 0.041 0 100 0.1115 0.7692 0.0386 0.0057 300 0.0378 0.2486 0.0177 0.0031 300 0.0406 0.2483 0.0174 0.0052 900 0.0179 0.0851 0.012 0.0039 900 0.018 0.0863 0.0128 0.0055 2700 0.0111 0.036 0.0094 0.0041 2700 0.0113 0.0325 0.0094 0.005

Supernatant was then tested by competition ELISA to determine if the signals were specific to olanzapine. FIGS. 1-3 show the results from three representative hybridomas resulting from mouse fusion 11.1 (olanzapine immunogen having Formula II). Data shows specific reactivity to olanzapine with varied reactivity to clozapine.

FIG. 4 shows the competitive immunoassay format used on a lateral flow assay device in which the capture antibody, an olanzapine clone, was deposited on a chip along with a detection conjugate consisting of olanzapine conjugated to a fluorophore. In this competitive format as show in FIG. 4, a low level of analyte (olanzapine) results in high signal, whereas a high level of analyte (olanzapine) results in low signal. The amount of olanzapine in the sample can be calculated from the loss of fluorescence compared to a control sample with no drug present. A typical dose response curve generated with olanzapine clone 35 is shown in FIG. 5, with olanzapine clone 61 is shown in FIG. 6, and with olanzapine clone 3F11 is shown in FIG. 7.

FIG. 8 shows the chip design of a lateral flow assay device according to one embodiment of the subject invention. The device includes a zone or area for receiving the sample, a conjugate zone (which contains desired labeled competitive binding partner(s)), and a reaction zone (eight areas within the reaction zone are indicated; each area can contain a separate desired antibody). Sample flows from the sample zone through the conjugate zone and to the reaction zone.

FIGS. 9-12 show typical dose response curves for an aripiprazole positive control (sample containing aripiprazole) generated with antibody 5C7 deposited in reaction zone 2 and a labeled aripiprazole competitive binding partner in the conjugate zone (FIG. 9), an olanzapine positive control (sample containing olanzapine) generated with antibody 4G9-1 deposited in reaction zone 4 and a labeled olanzapine competitive binding partner in the conjugate zone (FIG. 10), a quetiapine positive control (sample containing quetiapine) generated with antibody 11 deposited in reaction zone 6 and a labeled quetiapine competitive binding partner in the conjugate zone (FIG. 11), and a risperidone positive control (sample containing risperidone) generated with antibody 5-9 deposited in reaction zone 8 and a labeled risperidone competitive binding partner in the conjugate zone (FIG. 12). The labeled competitive binding partners in the conjugate zone compete with the drugs present in the samples for binding to the antibodies. The amount of label is detected and is an indication of the amount of drug present in the sample (the amount of signal being inversely proportional to the amount of drug in the sample—see FIG. 4).

In order to confirm that conjugates of labeled competitive binding partners do not bind to antibodies deposited in the reaction zones, negative controls were conducted by using samples containing no drugs. Referring to Table 10, a sample containing no aripiprazole is deposited in the sample zone and moves by capillary action through the conjugate zone (this time containing labeled olanzapine, labeled quetiapine, and labeled risperidone, but no labeled aripiprazole) and to the reaction zone. The reaction zone again contains aripiprazole antibody (5C7) in reaction zone 2. Table 10 below shows the results, confirming that there is no dose response and the olanzapine, quetiapine, and risperidone conjugates that move by capillary action through the reaction zone do not bind to the aripiprazole antibody.

TABLE 10 Aripiprazole-Clone 5C7-Math Model 1 (0 ng/mL Conc.) Reaction Read Peak Mean Peak Mean Mean Assay-MM Conj Zone Position Area Height Background ARIP-MM1 OLAN, QUET, RISP ARIP 2 0.77 1.56 3.99 ARIP-MM1 OLAN, QUET, RISP 4 −0.02 0.06 4.14 ARIP-MM1 OLAN, QUET, RISP 6 0.09 0.10 4.29 ARIP-MM1 OLAN, QUET, RISP 8 0.13 0.12 4.61 Other Conjugates do not bind to Aripiprazole

Referring to Table 11, a sample containing no olanzapine is deposited in the sample zone and moves by capillary action through the conjugate zone (this time containing labeled aripiprazole, labeled quetiapine, and labeled risperidone, but no labeled olanzapine) and to the reaction zone. The reaction zone again contains olanzapine antibody (4G9-1) in reaction zone 4. Table 11 below shows the results, confirming that there is no dose response and the aripiprazole, quetiapine, and risperidone conjugates that move by capillary action through the reaction zone do not bind to the olanzapine antibody.

TABLE 11 OLAN-Clone 4G9-1-Math Model 1 (0 ng/mL Conc.) Reaction Read Peak Mean Peak Mean Mean Assay-MM Conj Zone Position Area Height Background OLAN-MM1 ARIP, QUET, RISP 2 −0.03 0.05 4.38 OLAN-MM1 ARIP, QUET, RISP OLAN 4 0.74 1.10 4.56 OLAN-MM1 ARIP, QUET, RISP 6 0.06 0.09 4.79 OLAN-MM1 ARIP, QUET, RISP 8 0.11 0.13 5.17 Other Conjugates do not bind to Olanzapine

Referring to Table 12, a sample containing no quetiapine is deposited in the sample zone and moves by capillary action through the conjugate zone (this time containing labeled aripiprazole, labeled olanzapine, and labeled risperidone, but no labeled quetiapine) and to the reaction zone. The reaction zone again contains quetiapine antibody (11) in reaction zone 6. Table 12 below shows the results, confirming that there is no dose response and the aripiprazole, olanzapine, and risperidone conjugates that move by capillary action through the reaction zone do not bind to the quetiapine antibody.

TABLE 12 Quetiapine-Clone 11-Math Model 1 (0 ng/mL Conc.) Reaction Read Peak Mean Peak Mean Mean Assay-MM Conj Zone Position Area Height Background QUET-MM1 ARIP, OLAN, RISP 2 −0.01 0.07 3.85 QUET-MM1 ARIP, OLAN, RISP 4 0.01 0.12 4.01 QUET-MM1 ARIP, OLAN, RISP QUET 6 0.03 0.08 4.24 QUET-MM1 ARIP, OLAN, RISP 8 0.04 0.07 4.56 Other Conjugates do not bind to Quetiapine

Referring to Table 13, a sample containing no risperidone is deposited in the sample zone and moves by capillary action through the conjugate zone (this time containing labeled aripiprazole, labeled olanzapine, and labeled quetiapine, but no labeled risperidone) and to the reaction zone. The reaction zone again contains risperidone antibody (5-9) in reaction zone 8. Table 13 below shows the results, confirming that there is no dose response and the aripiprazole, olanzapine, and quetiapine conjugates that move by capillary action through the reaction zone do not bind to the risperidone antibody.

TABLE 13 Risperidone-Clone 5-9-Math Model 1 (0 ng/mL Conc.) Reaction Read Peak Mean Peak Mean Mean Assay-MM Conj Zone Position Area Height Background RISP-MM1 ARIP, OLAN, QUET 2 0.02 0.11 7.43 RISP-MM1 ARIP, OLAN, QUET 4 0.05 0.14 7.73 RISP-MM1 ARIP, OLAN, QUET 6 0.20 0.19 8.11 RISP-MM1 ARIP, OLAN, QUET RISP 8 1.97 3.23 8.85 Other Conjugates do not bind to Risperidone

In order to confirm that conjugates of labeled competitive binding partners bind only to their respective antibodies deposited in the reaction zones, additional negative controls were conducted by again using samples containing no drugs. Referring to Table 14, a sample containing no aripiprazole is deposited in the sample zone and moves by capillary action through the conjugate zone (this time containing labeled aripiprazole) and to the reaction zone. The reaction zone again contains aripiprazole antibody (5C7) in reaction zone 2, as well as olanzapine antibody (4G9-1) in reaction zone 4, quetiapine antibody (11) in reaction zone 6, and risperidone antibody (5-9) in reaction zone 8. Table 14 below shows the results, confirming that there is no dose response except to the aripiprazole antibody 5C7 (in reaction zone 2).

TABLE 14 Aripiprazole-Clone 5C7-Math Model 1 (0 ng/mL Conc.) Peak Peak Reaction Read Mean Mean Mean Assay-MM Conj Zone Position Area Height Background ARIP-MM1 ARIP, OLAN, QUET, RISP ARIP 2 60.34 97.53 5.44 ARIP-MM1 ARIP, OLAN, QUET, RISP 4 2.86 3.91 11.66 ARIP-MM1 ARIP, OLAN, QUET, RISP 6 1.12 1.23 11.03 ARIP-MM1 ARIP, OLAN, QUET, RISP 8 3.14 4.19 12.94 Only the Aripiprazole Reaction Zone is binding

Referring to Table 15, a sample containing no olanzapine is deposited in the sample zone and moves by capillary action through the conjugate zone (this time containing labeled olanzapine) and to the reaction zone. The reaction zone again contains aripiprazole antibody (5C7) in reaction zone 2, as well as olanzapine antibody (4G9-1) in reaction zone 4, quetiapine antibody (11) in reaction zone 6, and risperidone antibody (5-9) in reaction zone 8. Table 15 below shows the results, confirming that there is no dose response except to the olanzapine antibody 4G9-1 (in reaction zone 4).

TABLE 15 OLAN-Clone 4G9-1-Math Model 1 (0 ng/mL Conc.) Peak Peak Reaction Read Mean Mean Mean Assay-MM Conj Zone Position Area Height Background OLAN-MM1 ARIP, OLAN, QUET, RISP 2 0.02 0.08 4.86 OLAN-MM1 ARIP, OLAN, QUET, RISP OLAN 4 34.23 51.80 5.39 OLAN-MM1 ARIP, OLAN, QUET, RISP 6 0.22 0.32 5.39 OLAN-MM1 ARIP, OLAN, QUET, RISP 8 0.15 0.17 5.59 Only the Olanzapine Reaction Zone is bindng

Referring to Table 16, a sample containing no quetiapine is deposited in the sample zone and moves by capillary action through the conjugate zone (this time containing labeled quetiapine) and to the reaction zone. The reaction zone again contains aripiprazole antibody (5C7) in reaction zone 2, as well as olanzapine antibody (4G9-1) in reaction zone 4, quetiapine antibody (11) in reaction zone 6, and risperidone antibody (5-9) in reaction zone 8. Table 16 below shows the results, confirming that there is no dose response except to the quetiapine antibody 11 (in reaction zone 6).

TABLE 16 Quetiapine-Clone 11-Math Model 1 (0 ng/mL Conc.) Peak Peak Reaction Read Mean Mean Mean Assay-MM Conj Zone Position Area Height Background QUET-MM1 ARIP, OLAN, QUET, RISP 2 0.13 0.41 10.02 QUET-MM1 ARIP, OLAN, QUET, RISP 4 0.08 0.23 10.47 QUET-MM1 ARIP, OLAN, QUET, RISP QUET 6 140.35 181.33 7.91 QUET-MM1 ARIP, OLAN, QUET, RISP 8 1.58 2.61 11.53 Only the Quetiapine Reaction Zone is binding

Referring to Table 17, a sample containing no risperidone is deposited in the sample zone and moves by capillary action through the conjugate zone (this time containing labeled risperidone) and to the reaction zone. The reaction zone again contains aripiprazole antibody (5C7) in reaction zone 2, as well as olanzapine antibody (4G9-1) in reaction zone 4, quetiapine antibody (11) in reaction zone 6, and risperidone antibody (5-9) in reaction zone 8. Table 17 below shows the results, confirming that there is no dose response except to the risperidone antibody 5-9 (in reaction zone 8).

TABLE 17 Risperidone-Clone 5-9-Math Model 1 (0 ng/mL Conc.) Peak Peak Reaction Read Mean Mean Mean Assay-MM Conj Zone Position Area Height Background RISP-MM1 ARIP, OLAN, QUET, RISP 2 1.03 1.51 9.07 RISP-MM1 ARIP, OLAN, QUET, RISP 4 0.65 0.91 9.60 RISP-MM1 ARIP, OLAN, QUET, RISP 6 2.61 6.39 10.48 RISP-MM1 ARIP, OLAN, QUET, RISP RISP 8 55.98 100.91 11.58 Only the Risperidone Reaction Zone is binding

The results shown above confirm that conjugates of labeled competitive binding partners bind only to their respective antibodies in the reaction zone.

FIGS. 13-16 show typical dose response curves in specific antibody reaction zones, and proof of dose response low/high concentration for each specific assay in the presence of other conjugates. In FIG. 13, a sample containing aripiprazole is deposited in the sample zone and moves by capillary action through the conjugate zone (this time containing labeled aripiprazole, labeled olanzapine, labeled quetiapine, and labeled risperidone) and to the reaction zone. The reaction zone again contains aripiprazole antibody (5C7) in reaction zone 2. A typical dose response curve was generated as is shown in FIG. 13 only for aripiprazole, and not for olanzapine, quetiapine, or risperidone.

In FIG. 14, a sample containing olanzapine is deposited in the sample zone and moves by capillary action through the conjugate zone (this time containing labeled aripiprazole, labeled olanzapine, labeled quetiapine, and labeled risperidone) and to the reaction zone. The reaction zone again contains olanzapine antibody (4G9-1) in reaction zone 4. A typical dose response curve was generated as is shown in FIG. 14 only for olanzapine, and not for aripiprazole, quetiapine, or risperidone.

In FIG. 15, a sample containing quetiapine is deposited in the sample zone and moves by capillary action through the conjugate zone (this time containing labeled aripiprazole, labeled olanzapine, labeled quetiapine, and labeled risperidone) and to the reaction zone. The reaction zone again contains quetiapine antibody (11) in reaction zone 6. A typical dose response curve was generated as is shown in FIG. 15 only for quetiapine, and not for aripiprazole, olanzapine, or risperidone.

In FIG. 16, a sample containing risperidone is deposited in the sample zone and moves by capillary action through the conjugate zone (this time containing labeled aripiprazole, labeled olanzapine, labeled quetiapine, and labeled risperidone) and to the reaction zone. The reaction zone again contains risperidone antibody (5-9) in reaction zone 8. A typical dose response curve was generated as is shown in FIG. 16 only for risperidone, and not for aripiprazole, olanzapine, or quetiapine.

FIGS. 17-20 show typical dose response curves for each assay in the presence of other conjugates and antibodies. In FIG. 17, a sample containing aripiprazole is deposited in the sample zone and moves by capillary action through the conjugate zone (again containing labeled aripiprazole, labeled olanzapine, labeled quetiapine, and labeled risperidone) and to the reaction zone. The reaction zone again contains aripiprazole antibody (5C7) in reaction zone 2, as well as olanzapine antibody (4G9-1) in reaction zone 4, quetiapine antibody (11) in reaction zone 6, and risperidone antibody (5-9) in reaction zone 8. A typical dose response curve was generated for aripiprazole, as is shown in FIG. 17. When a sample containing olanzapine was deposited in the sample zone of this chip, a typical dose response curve was generated for olanzapine as shown in FIG. 18. When a sample containing quetiapine was deposited in the sample zone of this chip, a typical dose response curve for quetiapine was generated as shown in FIG. 19. When a sample containing risperidone was deposited in the sample zone of this chip, a typical dose response curve for risperidone was generated as shown in FIG. 20.

FIGS. 21-24 show comparisons of dose response curves generated as positive controls (FIGS. 9-12) to dose response curves generated in the multiplex format (FIGS. 17-20). The comparison for aripiprazole is shown in FIG. 21; for olanzapine in FIG. 22; for quetiapine in FIG. 23; and for risperidone in FIG. 24. These figures show that the positive control curves are similar to the multiplex curves.

These data show that a lateral flow assay device of the subject invention can be used to detect multiple anti-psychotic drugs using a single sample from a patient on one portable, point-of-care device. 

What is claimed is:
 1. An immunoassay method for detecting an analyte comprising: (i) generating an antibody or a binding fragment thereof in response to a conjugate of a compound of Formula I and an immunogenic carrier,

wherein: R¹ is

CH₂NH₂, or CH₂NHC(O)(CH₂)₂CO₂H; R² is H; R³ is H; wherein: m is 1 or 5; and wherein the conjugate of the compound of Formula I and the immunogenic carrier is formed by attaching the immunogenic carrier to the substituent at the R¹ position of Formula I; (ii) contacting a sample with the antibody or binding fragment thereof labeled with a detectable marker, wherein the labeled antibody or binding fragment and the analyte present in the sample form a labeled complex; and (iii) detecting the labeled complex so as to detect the analyte in the sample.
 2. A competitive immunoassay method for detecting an analyte comprising: (i) generating an antibody or a binding fragment thereof in response to a conjugate of a compound of Formula I and an immunogenic carrier,

wherein: R¹ is

CH₂NH₂, or CH₂NHC(O)(CH₂)₂CO₂H; R² is H; R³ is H; wherein: m is 1 or 5; and wherein the conjugate of the compound of Formula I and the immunogenic carrier is formed by attaching the immunogenic carrier to the substituent at the R¹ position of Formula I; (ii) attaching to a solid support (a) the antibody or binding fragment thereof, or (b) the analyte or a competitive binding partner of the analyte; (iii) passing a sample and a labeled component through the solid support, wherein the labeled component is (a) the analyte or the competitive binding partner of the analyte attached to a detectable marker, when the antibody or binding fragment thereof is attached to the solid support, or (b) the antibody or binding fragment thereof attached to the detectable marker, when the analyte or a competitive binding partner of the analyte is attached to the solid support; and (iv) detecting the detectable marker.
 3. The method of claim 2, wherein the analyte or competitive binding partner thereof is labeled with the detectable marker.
 4. The method of claim 2, wherein the antibody is labeled with the detectable marker.
 5. The method of claim 2, wherein the immunoassay is performed on a lateral flow assay device and the sample is applied to the device.
 6. The method of claim 1, wherein the sample is a biologic sample from a patient and the method further comprises determining attainment of minimum pK levels of the analyte in the subject.
 7. The method of claim 1, wherein the method further comprises determining bioequivalence of the analyte in multiple formulations or from multiple sources based on the detection of the analyte.
 8. The method of claim 1, wherein the method further comprises including or excluding a patient into a clinical trial based on the detection of the analyte.
 9. The method of claim 2, wherein the sample is a biologic sample from a subject and the method further comprises determining the attainment of minimum pK levels of the analyte in the subject.
 10. The method of claim 2, wherein the method further comprises determining bioequivalence of the analyte in multiple formulations or from multiple sources based on detecting the presence of the analyte.
 11. The method of claim 2, wherein the method further comprises including or excluding a patient in a clinical trial based on detecting the presence of the analyte.
 12. The method of claim 1, wherein the conjugate of a compound of Formula I and the immunogenic carrier has the following structure:


13. The method of claim 1, wherein the compound of Formula I is selected from the group consisting of:


14. The method of claim 2, wherein the conjugate of a compound of Formula I and the immunogenic carrier has the following structure:


15. The method of claim 2, wherein the compound of Formula I is selected from the group consisting of: 